COMPARATIVE ECOLOGY AND MIMETIC RELATIONSHIPS
OF ITHOMIINE BUTTERFLIES IN EASTERN ECUADOR
BOYCE ALEXANDER DRUMMOND III
A DISSERTATION PRESENTED TO THE GRADUATE COUNCIL
OF THE UNIVERSITY OF FLORIDA
IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE
DECREE OF DOCTOR OF PHILOSOPHY
UNIVERSITY OF FLORIDA
as she lays aside her net awhile to take up the caduceus
It is my pleasure to thank the members of my committee, Drs. Thomas
C. Emmel, Archie Carr, Clifford Johnson, and Thomas Walker, for the
guidance and encouragement they have provided throughout my graduate
career. I have profited greatly from their respective graduate courses
and from the exposure to their divergent, but complementary, approaches
to biology. I also thank Drs. John Ewel, Dana Griffin, and Jon Reiskind
for helpful discussions and much useful information during the writing
of this dissertation.
For the countless ways in which they have assisted in all phases
of the research reported here, I profess my deepest appreciation to Dr.
Thomas Emmel, chairman of my committee, and Nancy Drummond, my wife and
field assistant. Without the benefit of their help, many of the goals
of this project could not have been accomplished. To Dr. Emmel, who
first introduced me to tropical ecology and kindled my interest in the
biology of the Lepidoptera, I am indebted for the constant personal,
academic, and financial support he so graciously proffered. My wife,
Nancy, whose great enthusiasm for our year of field work in Ecuador
was matched only by her unflagging patience during the tedious year and
a half that followed in Gainesville, assisted in the collection of
specimens and population samples, handled most of the life-history
hearings, and aided in the preparation and analysis of the data. For
all this and much more I am thankfully beholden.
I am grateful to Dr. William G. D'Arcy, Missouri Botanical Garden,
St. Louis, for identifying the solanaceous plants. At the Allyn
Museum of Entomology, Sarasota, Florida, Dr. Lee Miller aided in the
identification of several butterfly species and Jacqueline Miller
kindly identified the Castniidae. I am indebted to Dr. Lincoln Brower,
Amherst College, for loaning me a copy of Christine Papageorgis'
dissertation, and to F. Martin Brown, Colorado Springs, Colorado, for
loaning me one of the few extant copies of d'Almeida's "Melanges
Lepidopteriques." I thank my wife, Nancy, for translating the latter
work and other papers from the French. Nancy Drummond also patiently
typed and edited early drafts of the manuscript as well as most of the
final copy, for which I am extremely grateful. Donna Gillis
typed Tables 4 and 5 and the bibliography. The photography staff of the
Office of Instructional Resources, University of Florida, prepared
Figures 10 through 15. Nancy Drummond kindly drew Figures 33-35 and
46-47 and aided in the preparation of several others.
The year of Ecuadorian field work was made possible only by the
aid of a number of helpful persons and organizations in the United
States and Ecuador. Dan Doyle of the Miami office of the Summer
Institute of Linguistics severed yards of red tape at the Ecuadorian
embassy to expedite the issuance of the required visas. Giovanna
Holbrook of Holbrook Travel and the staff of JAARS (Jungle Aviation and
Radio Service of SIL) kindly arranged the various transfers of our over-
weight equipment and baggage to, from, and within Ecuador against
improbable odds. Ruth and Steve Smith kindly stored our worldly
possessions during our fourteen months in Ecuador. The personnel of
the Ecuadorian Branch of the Summer Institute of Linguistics, especially
John Lindskoog, Jonathon Johnson, and Don and Helen Johnson, facilitated
our transportation in Ecuador and made available housing and supplies
at Limoncocha. I am particularly grateful to Wayne and JoAnne Fitch,
Jim and Kathie Yost, and Pat Kelley for many personal favors during
the course of this research. Special thanks are due Mark and Phyllis
Newell for allowing us to live in their spacious house at Limoncocha
during the final three months of our stay. I thank Drs. Howard Weems
and Robert Woodruff, Department of Entomology, Division of Plant
Industry, Florida Department of Agriculture, for providing equipment
and supplies. This research was supported in part by a Grant-in-Aid
from Sigma Xi.
TABLE OF CONTENTS
ACKNOWLEDGMENTS . . . . . .
LIST OF TABLES . . . . . . .
LIST OF FIGURES . . . . . . .
ABSTRACT . . . . . . . .
I INTRODUCTION . . . . . . .
Study Area . . . . . .
Historical Background ..
Climatic Description . . .
Physical Description . . .
The Butterfly Community at Limoncocha
Composition . . . . .
Microhabitat Distribution . .
The Butterfly Subfamily Ithomiinae .
The Plant Family Solanaceae . .
II METHODS . . . . . . . .
III ADULT ECOLOGY OF THE ITHOMIINAE . . .
Microhabitat Requirements ..
Activity Patterns . . . . .
Perching Behavior . . . . .
Predation and Parasitism . . .
Food Resources and Feeding Behavior
Locating Food Sources ..
Flower Feeding . . . . .
Coevolution of Ithomiines and
White-flowered Plants . ..
Ithomiine Attraccants . . .
. . . . . iii
. . . . . ix
. . . . . xi
. . 1
. . 59
. . 71
Population Ecology . . . . . . .
Spatial Heterogeneity . . . . .
The Capture-Mark-Recapture Program
at Site 4 . . . . . . . .
IV REPRODUCTIVE BIOLOGY OF THE ITHOMIINAE . . .
Courtship . . . . . . . . .
Function of Hairpencils in Male Ithomiines
Mate-locating Behavior of Male Butterflies
Mate-locating Behavior of Ithomiine Males
Species-specific Male Courtship Behaviors
Pursuit Behavior of Courting Males .
Function of the Display Perch . .
Mating . . . . . . . . .
Sperm Precedence . . . . .
Multiple Matings . . . . .
Carrying Pair Behavior . . . .
Oviposition . . . . . . .
Oviposition Strategies . . .
Modes of Oviposition Behavior . .
Foodplant Specificity . . . .
V COMPARATIVE LIFE HISTORIES OF THE I1
Immature Stages . . . .
Eggs . . . . .
Larvae . . . . .
Pupae . . . . .
Generation Time . . . .
Parasitism and Predation . .
Parasitism . . . .
Predation . . . .
r II- lrl'fl TFllnIT TtlA f mi *%Ar r1 T,.lrflfnlrf lr
VI In. I ilnurl HIL .-l.u t tLN IN i .i r . . . . . .
Plant Defenses and Larval Adaptations . . .
Larval Foodplant Relationships of the Ithomiinae
Patterns of Foodplant Utilization . . .
Foodplant Specificity of Limoncocha Ithomiines
Utilization of Larval Foodplants at Limoncocha .
VII THE MIMETIC RELATIONSHIPS OF THE ITHOMIINAE . . .
The Mimetic Subcomplexes at Limoncocha . . .
Transparent Mimetic Complex . . . . .
Tiger Mimetic Complex . . . . . .
: : : :
Polymorphic Mimetic Species . . . .. 326
Ithomiine Participation in Limoncocha
Mimicry Complexes . . . . . . . 329
Evidence for Unpalatability in the Ithomiinae . 331
Circumstantial' Evidence . . . . . ... 331
Direct Evidence . . . . . . . ... 334
Some Mimetic Consequences of Ithomiine Ecology . . 335
VIII CONCLUSIONS . . . . . . . . . . . . 344
REFERENCES . . . . . . . . . . . . . . 349
BIOGRAPHICAL SKETCH . . . . . . . . . . . 361
LIST OF TABLES
1. Water Balance Calculation for Limoncocha, Ecuador . .
2. Comparison of the Butterfly Faunas of a Variety
of Neotropical Locations . . . .. . . .
3. The Number of Genera and Species in the Eight Tribes
of Ithomiinae . . . . . . . . . .
4. Species of Ithomiinae Collected at'Limoncocha, Ecuador .
5. Species of Solanaceae Collected at Limoncocha, Ecuador .
6. Nectar Sources of Ithomiine Butterflies . . . .
7. Summary of Collections of Ithomiine Butterflies Visiting
Eupatorium I Flowers at Study Sites 1 and 3 in
January 1974 . . . . . . . . . .
8. Species Diversity of the Ithomiine Community at
Study Site 4 . . . . . . . . . .
9. Similarity of Species Composition Between Consecutive
Samples of the Ithomiine Community at Study Site 4
(Sarenson's Quotient of Similarity) . . . . .
10. Estimates of Longevity of Ithomiine Butterflies Based
on Recapture Data at Study Site 4 . . . . .
11. Sex Ratio, Probability of Interspecific Encounter (PIE),
and Probability of Intraspecific-heterosexual Encounter
in the Ithomiine Community at Study Site 4 . . .
12. Postures of Male Ithomiines During Display
Perch Courtship . . . . . . . . . .
13. Postures of Male Ithomiines During Patrol
Perch Courtship . . . . . . . . . .
14. Mating Pairs of Ithomiines Observed at Limoncocha . .
15. Summary of Oviposition Parameters for Ithomiine
Butterflies . . . . . . . . . . .
16. Summary of Developmental Times of Ithomiine
Butterflies . . . . . . . . . . .
17. Parasitism of Field-collected Ithomiine Eggs and
Larvae . . . . . . . . . . .
18. Larval Foodplant Records for the Ithomiidae . . .
19. Numbers of Solanaceous Plants and Ithomiine Immatures
at Site 4 . . . . . . . . . . .
20. Numbers of Solanaceous Plants and Ithomiine Immatures
at Site 5 . . . . . . . . . . .
21. Numbers of Solanaceous Plants and Ithomiine Immatures
at Site 1 . . . . . . . . . . .
22. Numbers of Solanaceous Plants and Ithomiine Immatures
at Site 6 . . . . . . . . . . .
23. Summary of Foodplant and Juvenile Ithomiine Densities
24. Ithomiine Participation in Limoncocha Mimicry Complexes
LIST OF FIGURES
1. Map of East Ecuador (the Oriente) . . . . . .. 5
2. Map of Limoncocha, Ecuador . . ... .. . . ... .7
3. Mean Monthly Temperatures, Mean Monthly Maximum Temperatures,
and Mean Monthly Minimum Temperatures at Limoncocha,
Ecuador . ... . . . . . ........... 10
4. Annual Rainfall at Limoncocha, Ecuador: 1961-1974 ... 11
5. Mean Monthly Rainfall at Limoncocha, Ecuador . . . .. 13
6. Rainfall at Limoncocha, Ecuador:
January 1974 to December 1974 . . . . . .. 13
7. Percent Rainy Days per Month and Mean Maximum Consecutive
Rainless Days per Month at Limoncocha, Ecuador .... 14
8. Percent Days per Month with Greater Than 50% Cloud Cover
at 1300 hours at Limoncocha, Ecuador . . . ... 15
9. Mean Monthly Percent Relative Humidity at 1300 hours at
Limoncocha, Ecuador . . . . . . . . ... .16
10. Near Beginning of Nature Trail (stem portion) in
Secondary Forest . . . . . . . .... . 25
11. Nature Trail (loop portion) in Primary Forest, near
Study Site 4 (100 m by 2 m transect) . . . ... .25
12. Logging Trail, Study Site 3 . . . . . . .... .27
13. Males of Scada batesi Haensch Feeding at Eupatorium I
Flowers at Study Site 3 . . . . . . . ... 27
14. Logging Trail, Study Site 4 . . . . . . .... .29
15. Forest Interior at Study Site 4 . . . . . ... 29
16. Number of Species in each Butterfly Family at
Limoncocha, Ecuador . . . . . . . . ... .36
17. Number of Species in each Butterfly Family in
Eastern Pernambuco, Brazil . . . . . . .
18. Number of Species in each Butterfly Family in Eastern
Espfrito Santo and Southern Bahia, Brazil . . . .
19. Number of Species in each Butterfly Family at
Jaru, Rondonia, Brazil . . . . . . . .
20. Relative Abundances of Species of Ithomiinae at Limoncocha
Ecuador . . . . . . . . . . . .
21. Ithomiine Feeding Activity at Heliotropium I Blossoms:
June 26, 1974 . . . . . . . . . . .
22. Ithomiine Feeding Activity at Heliotropium I Blossoms:
June 29, 1974 . . . . . . . . . . .
23. Ithomiine Feeding Activity at 4aranta I Blossoms:
July 12, 1974 . . . . . . . . . . .
24. Ithomiine Feeding Activity at Eupatorium II Blossoms:
July 12, 1974 . . . . . . . . . . .
25. Associations of Species of Ithomiines with Microhabitat
Regions of the Nature Trail Observation Area ..
26. Distribution of Captured Ithomiine Individuals Among the
50 Subplots at Study Site 4 . . . . . . .
27. Summary Graph of the 26 Ithomiine Samples Taken at
Study Site 4 . . . . . . . . . .
28. Species and Individuals Present in the 26 Ithomiine
Samples Taken at Study Site 4 . . . . . . .
29. Equitability (J') and Quotient of Similarity (QS) Values f(
the 26 Ithomiine Samples Taken at Study Site 4 . .
30. Regression of the Quotient of Similarity (QS) on Sample
Size (N) . . . . . . . . . . .
31. Age Class Distribution of the Ithomiine Community at
Study Site 4 . . . . . . . . . . .
32. Courtship Activity of Male Ithomiines . . . . .
33. Location and Erection of Hairpencils in Male Ithomiines
34. Napeogenes apobsoleta in Display Perch
Courtship Behavior . . . . . . . . .
35. Mechanitis messenoides in Patrol Perch
Courtship Behavior . . . . . . . .
36. Perch Height versus Time of Day for all Courting
Male Ithomiines . . . . . . . . . .
37. Perch Height versus Time of Day for Display-Perching
Male Ithomiines in the Yellow Clear-wing Mimetic
Subcomplex . . . . . . . . . . .
38. Perch Height versus Time of Day for Display-Perching Male
Ithomiines in the Tiger Mimetic Complex . . . .
39. Perch Height versus Time of Day for Patrol-Perching Male
Ithomiines in the Tiger Mimetic Complex . . . .
40. Ethnograms of Eight Species of Display-Perching
Ithomiine Males . . . . . . . . . .
41. Ethnograms of Three Species of Patrol-Perching
Ithomiine Males . . . . . . . . . .
42. Mating Activity of Ithomiines . . . . . . .
43. Oviposition Activity of Female Ithomiines . . . .
44. Summary of Ithomiine Reproductive Activities . . . .
45. Egg Volume versus Female Forewing Length . . . . .
46. Modes of Ithomiine Oviposition Behavior . . . . .
47. Illustrations of Some Eggs, Larvae, and Pupae of
Ithomiines . . . . . . . . . . .
48. Generation Times of 34 Species of Ithomiinae . . . .
49. Comparative Developmental Times Among Ithomiine Tribes .
50. Egg Volume versus Egg Development Time . . . . .
51. Mature Larval Length versus Larval Development Time . .
52. Egg Volume versus Generation Time . . . . . .
53. Mature Larval Length versus Generation Time . . . .
54. Larval Foodplant Relationships of Ithomiine Tribes .... 284
55. Larval Foodplants of Limoncocha Ithomiinae . . . ... 287
56. Numbers of Solanaceous Foodplants Utilized by Species
of Ithomiinae at Limoncocha . . . . . . ... 290
57. Numbers of Ithomiinae Supported by Species of Solanaceae
at Limoncocha . . . . . . . . ... . . 290
58. Transparent Mimetic Complex: Yellow Opaque Subcomplex and
Orange-Tip Subcomplex . . . . . . . ... 305
59. Transparent Mimetic Complex: White Subcomplex ...... 307
60. Transparent Mimetic Complex: Yellow Clear-wing
Subcomplex . . . . . . . . ... .... . 309
61. Transparent Mimetic Complex: Large Clear-wing Subcomplex 311
62. Tiger Mimetic Complex: Black, Yellow, and Orange
Understory Subcomplex . . . . . . . ... 317
63. Tiger Mimetic Complex: Yellow-Bar Canopy Subcomplex . . 319
64. Tiger Mimetic Complex: Yellow-Spot Canopy Subcomplex . 321
65. Tiger Mimetic Complex: Orange and Black Subcomplex . . 323
66. Abundances of Transparent Mimetic Subcomplexes at
Study Site 4 . . . . . . . . ... . . 338
67. Abundances of Tiger Mimetic Subcomplexes at Study
Site 4 . . . . . . . . ... .. . . 340
68. Summary of the Abundances of the Transparent and Tiger
Mimetic Complexes at Study Site 4 . . . . . . 342
Abstract of Dissertation Presented to the Graduate Council
of the University of Florida in Partial Fulfillment of the Requirements
for the degree of Doctor of Philosophy
COMPARATIVE ECOLOGY AND MIMETIC RELATIONSHIPS
OF ITHOMIINE BUTTERFLIES IN EASTERN ECUADOR
Boyce Alexander Drummond III
Chairman: Thomas C. Emmel
Major Department: Zoology
Butterflies of the subfamily Ithomiinae (Lepidoptera, Ithomiidae) are
among the most conspicuous and abundant flying insects of neotropical forests,
yet they have received little attention from ecologists and their biology
is not well known. A comprehensive ecological study of a rich (53 species)
ithomiine community (in lowland rainforest at Limoncocha, on the Rio
Napo, eastern Ecuador) was combined with an extensive search of the
literature to characterize this subfamily in ecological terms.
Ithomiines usually exhibit clumped distribution, even within seemingly
homogeneous forests, where their responses to gradients of light and rela-
tive humidity result in transient concentrations that crest and ebb through
time. Ithomiines are long-lived, with low daily rates of oviposition
and adult-financed egg production. The early morning visits of ithomiine
males to white flowers fit the syndrome of crepuscular pollination and
may represent a coevolved relationship. Females feed on detritus from
which they apparently obtain the nitrogen needed for continuous egg
production. Courtship behavior is species-specific and involves two
categories of mate-locating behavior by males, "display perching" and
"patrol perching." The oviposition strategies of ithomiine females
vary greatly and four modes of oviposition behavior are recognized.
The adaptive significance of extended copulation in butterflies is
Local populations of most ithomiine species appear to be narrowly
specific in larval foodplant utilization, and the high diversity of the
ithomiine community is probably due in large part to the high diversity
of the larval foodplants (Solanaceae) in tropical forests. Larval
development time depends on the mechanical and chemical characteristics
of the foodplant, but the average generation time is about 28 to 30
days. Juvenile ithomiines display great interspecific variation in
morphology in all life stages. The similarity of the previously unde-
scribed larva of Melinaea menophilus (Ithomiidae) to larvae of other
primitive ithomiines and to larvae of the Danaidae provides new evidence
for the relationship between the two families.
'A nine-month censusing program at Limoncocha revealed that the
ithomiine adult community appears to be quite stable in relative composi-
tion of mimetic patterns, age distribution, species diversity (H'), and
equitability (J'). Larval foodplants are greatly under-utilized at
Limoncocha and intensive parasitism and predation of juvenile stages
appear to be controlling the population sizes of most ithomiine species,
although the overall abundance of the ithomiine community may be severely
depressed by the indiscriminate adult mortality resulting from violent
storms and periods of heavy rainfall.
Community ecology may be defined as the study of the relationships
among a set of coexisting interdependent populations (Price, 1975).
Early studies usually concentrated on communities defined largely by
spatial constraints, e.g., a field, a rotting log, an algal mat, or
any unit that contained several species. More recently, however, seg-
ments of a community that contain biologically or evolutionarily closely
related species have been employed as a means of studying the ecological
relationships of a community. For example, Root (1967) has introduced
the concept of the guild, a group of species (i.e., a set of populations)
that exploits the same class of environmental resources in a similar
manner. A guild, then, contains species that are ecologically similar,
but may be taxonomically diverse. Another approach involves the study
of a taxonomic segment of a community, or taxocene (Chodorowski, 1959;
Hutchinson, 1967), the members of which are likely to be of about the
same size, to have similar life histories, and to compete over both
evolutionary and ecological time (Deevey, 1969). This combination of
characteristics suggests that comparative studies, both among the species
within a taxocene and among taxocenes themselves, should be particularly
useful in elucidating community structure. Although taxocenes can be
defined at several levels, the broader the taxonomic category employed,
the less similar the included species will be, and thus the more diffi-
cult meaningful comparisons will become. The size and uniformity of the
spatial or environmental dimension of a taxocene is determined by the
organisms' size, mobility, and fidelity to particular microhabitats
The present study is an attempt to better understand the butterfly
community of a neotropical lowland rainforest through a comparative
study of species of the subfamily Ithomiinae (Lepidoptera: Papilionoidea:
Ithomiidae), a group of butterflies that closely fits Deevey's descrip-
tion of a taxocene. The ithomiine taxocene is attractive for such a
study for several reasons. Although closely related and morphologically
similar, ithomiines differ enough in wing pattern, behavior, and repro-
ductive strategy to permit meaningful comparative studies of species
that compete over both evolutionary and ecological time. As a group,
ithomiines are relatively abundant in neotropical rainforests, and the
flight levels of most species make them accessible for detailed study.
As adults, they are the most numerous participants in the extensive and
widespread mimicry complexes of neotropical forests. As herbivorous
immatures, they are known to specialize almost exclusively on a plant
taxocene, the Solanaceae, that is notorious for the diversity of its
mechanical and chemical anti-herbivore devices. Such a relationship
suggests that the study of the Ithomiinae-Solanaceae interface could
provide extremely fertile ground in which to cultivate the theories of
And yet, for all this, the Ithomiinae have received only scant at-
tention from ecologists. In a preliminary study, Gilbert (1969) assessed
their suitability for answering certain questions about community ecol-
ogy. More recently, Young (1972, 1974a,b,c) has published life histories
of four species of Ithomiinae from Cuesta Angel, a montane forest
locality in Costa Rica, and thus has laid the foundation for a detailed
comparative study there. Pliske (1975a,b,c; Pliske et al., 1976) has
begun an investigation into the role of olfactory communication in the
behavioral ecology of adult Ithomiinae. In addition, some ecological
information may be gleaned from a few scattered observations in the early
literature (e.g., Collenette and Talbot, 1928) and from some recent
studies of mimicry complexes involving ithomiines (Poole, 1970; Papageor-
gis, 1974; Brown and Benson, 1974). In spite of these studies, however,
the Ithomiinae remain poorly understood ecologically.
Thus, in addition to using the Ithomiinae as a taxocene to approach
butterfly community ecology, a main goal of this study is to increase
the body of knowledge about the Ithomiinae, both to adequately character-
ize the subfamily in ecological terms and to determine promising direc-
tions for future research.
The lowland tropical forests of eastern Ecuador (the Oriente) form
the western extremity of that vast sea of tropical vegetation known as
Amazonas, or the Amazon Basin. Drained primarily by the Napo and Pastaza
Rivers and their numerous tributaries, the Oriente corresponds roughly
to the western half of the largest and ecologically most diverse of the
several lowland tropical refugia postulated to have harbored tropical
forest floral and faunal elements during glacial periods of the Quater-
nary. Named after the largest river in the Oriente, the Napo Refuge
comprised mainly the lowlands of east Ecuador (prior to the political
rearrangements of the 1942 Protocolo de Rio de Janeiro which ceded much
of this area to Peru) from the Andes east to the upper Amazon (Haffer,
1974). The evolutionary significance of these Quaternary Refugia will
be discussed later in this paper, but it can be noted now that the size
and structural diversity of the. Napo Refuge was probably responsible in
part for the high species richness that occurs in this region at the
present. The study area for this research, Limoncocha, in Napo Province,
Ecuador, is located within the boundaries of the Napo Refuge.
Limoncocha is the field headquarters for the linguistic, education-
al, and cultural work in eastern Ecuador of. the Summer Institute of Lin-
guistics (known in the United States as the Wycliffe Bible Translators),
a nondenominational missionary organization that operates under contract
with the Ministry of Education of the Ecuadorian government. Situated
at 00 24' South latitude and 760 38' West longitude, Limoncocha is lo-
cated about 210 kilometers almost due east of Quito on the western edge
of "Lemon Lake," an oxbow cut-off of the Rio Napo that lies two kilome-
ters to the south. The Limoncocha area is bordered on the west by the
Rio Jiveno (see map, Figure 1).
When the Summer Institute of Linguistics (S.I.L.) selected this
site in 1957 as a logistic support base for its personnel working with
isolated indigenous Indian tribes (Cofan, Secoya-Siona, Shuara=Jivaro,
Waodani=Auca, Yumbo) in the Oriente, virgin forest covered the entire
area and there were no Indians living in the vicinity, although the re-
mains of pre-colonial villages have since been found on the lake's west-
ern edge. Since those humble beginnings, when tools and supplies were
flown in by amphibious plane, Limoncocha has grown into a sophisticated
settlement, complete with electricity from a diesel-powered generator
(operated 0700-2100 daily) and indoor plumbing. The twenty or so mis-
sionary families that presently live and work at Limoncocha are supplied
by weekly flights of the Institute's own DC-3 which lands on the 1100
meter airstrip completed in the mid-1960s (see map, Figure 2). The only
other access to Limoncocha is by canoe from Coca, the terminus of the
oil pipeline road built a decade ago by Shell-Texaco to exploit the con-
siderable oil reserves of the Oriente (see map, Figure 1).
During the 1960s, the rapid physical growth of the missionary base
at Limoncocha was accompanied by the coalescence of the scattered low-
land Quichua (=Yumbo) Indian families of the area into a village just
south of the airstrip. As both the village and the missionary settle-
ment grew, increasing demands were made on the surrounding forest, first
for lumber and game, and then for cleared land for crops and pasturage.
While the entire area within a ten kilometer radius has been heavily
hunted and selectively logged, clearing of the land for yuca (=manioc)
and banana fields had, until recently, been limited to the area between
Limoncocha and the Napo, especially along the "Napo Road" and the lower
Rio Jiveno (see map, Figure 2). More recently, however, the Ecuadorian
government has initiated a colonization program that offers 50-hectare
land grants to "colonistas" who settle in the Oriente, an effort designed
to help alleviate the burgeoning overpopulation of the highlands by en-
couraging eastward migration. The Limoncocha area has many attractions
for these colonistas, including two rivers and one lake for fishing,
availability of medical and dental care (two Registered Nurses reside at
the missionary settlement), and Limoncocha's growing importance as a
transportation center. In addition to the Quito-based DC-3, the Insti-
tute maintains two Heliocourier aircraft at Limoncocha for shuttling
PRIM A R
X7 ,S-Q "PT- -I 1
Map of Limoncocha, Ecuador.
translators to and from tribal areas and for transporting Indians into
Limoncocha for various educational programs and for medical care. The
synergistic effect of the government's colonization program and Limon-
cocha's attractiveness as a settlement area presents an ever-increasing
demand on the terrestrial and aquatic ecosystems of the area. At the
present rate of growth there will be very few--if any--undisturbed for-
est areas within a 15 kilometer radius of Limoncocha by 1980. Conse-
quently, as the land is cleared or otherwise disturbed, Limoncocha's val-
ue as a site for tropical scientific research will continue to diminish
Weather records (rainfall, maximum and minimum temperature, rela-
tive humidity and cloud cover) have been kept by S.I.L. and Ecuadorian
military personnel at Limoncocha since 1961. Monthly and yearly means
based on the first 14 years (1961-1974) of Limoncocha weather data fall
well within the ranges of values given by Richards (1964) as characteris-
tic of lowland tropical rain forests. Such forests are characterized by
a high mean annual temperature with little seasonal variance, relatively
heavy rainfall in all months of the year, high humidity, low wind veloc-
ity except during storms, and frequent cloudiness.
Prior to this study, Limoncocha had hosted a number of visiting scien-
tists, usually for visits of only one or two weeks. In addition, at least
three long-term studies had been conducted at Limoncocha; one on soil com-
position, one on bird foraging strategy, and a third on army ant behavior.
Mean annual temperature at Limoncocha is 25.20C, with the range
among monthly means less than 20C. The mean annual maximum tempera-
ture is 29.8C and the mean annual minimum temperature is 20.6C, a dif-
ference of less than 10C. The mean monthly maximum, mean monthly min-
imum and mean monthly temperatures are graphed in Figure 3.
The mean total annual rainfall is 3065 millimeters (range: 2600 to
3725 mm). If total annual rainfall is plotted on a yearly basis from
1961 to 1974, the resulting histogram gives some indication that annual
rainfall at Limoncocha is increasing (Figure 4). Although this apparent
increase may be only a portion of a much longer regional rainfall cycle,
or merely chance variation, Emmel (1974) has suggested that the increase
may be correlated with the "burning-off" of the new oil wells opened to
the northeast of Limoncocha in the early part of this decade. The par-
ticulate matter lofted upward in the form of smoke from the burning
wells may serve as nuclei for condensation and thus lead to an increase
in precipitation. It is true that the mean annual rainfall for the years
1961-1970 (2935 mm) is considerably less than the same statistic for the
period after 1970 (3390 mm), but the range of variation during the 14
years of records (1124 mm) is 2.5 times as great as the difference be-
tween these two means (456 mm). Several more years of data will be need-
ed to determine if the mean annual rainfall since the burn-off began
will stabilize around a new and significantly higher mean.
Although Limoncocha lies almost directly on the equator, where cli-
mate is theoretically seasonal, its weather data tend to support
Richards' (1964) statement that "there are probably no land surfaces
within the tropics with a completely seasonal rainfall." Limoncocha's
proximity to the equator insures that a substantial amount of rain falls
I I "a E
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Figure 5. Mean Monthly Rainfall at Limoncocha, Ecuador.
Figure 6. Rainfall at Limoncocha, Ecuador: January 1974 to
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
MAXIMUM NUMBER OF RAINLESS DAYS IN A ROW
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throughout the year, but there are rainfall maxima correlated with those
times at which the sun is at its zenith (mid-March and early October at
Limoncocha), with corresponding rainfall troughs inbetween. Thus, the
rainfall is distributed bimodally, with a broad peak in April-May-June
and a sharper peak in October (Figure 5). In spite of the considerable
variation in monthly rainfall totals from year to year, most of the 14
years for which data are available show this general pattern. The year
of this study, 1974, is an exception because of the unusually high rain-
fall in July-August-September (Figure 6). Indeed, 1974 had the highest
precipitation totals for August and September since record-keeping began.
The average percent rainy days per month (Figure 7) is closely cor-
related with average monthly rainfall. This suggests that the lower
rainfall of drier months is due more to the reduction in the number of
days with rain rather than in an overall decrease in the amount of rain
per day. Such a pattern allows the accumulation of several consecutive
rainless days to occur more often in the drier months, as the histogram
in Figure 7 shows.
Likewise, the degree of cloudiness and the percent relative humidity
also have a shallow bimodal pattern similar to that of rainfall. Cloud
cover, expressed as the percentage of days per month with greater than
4/8 cover at 1300 hours (Figure 8), is quite high, averaging above 70%
over the year. Relative humidity measurements are available for 0700,
1300, 1900 hours, but the 0700 readings are always 100% and the 1900
readings are usually 98-100% and never below 95%. The 1300 readings
show a very shallow deviation around a yearly mean of nearly 75% (Figure 9).
At Limoncocha, the temperature, rainfall and relative humidity mea-
surements were all taken one meter above the ground in a standard white
weather box located in the open on the airstrip. Comparative measure-
ments made with a sling psychrometer at the same height within mature
forest showed that relative humidity at 1300 hours was always substan-
tially higher than that recorded at the weather box. Rarely did the
relative humidity in mature forest fall below 85%. Likewise, tem-
peratures in the mature forest at 1300 hours were several degrees cooler
than those recorded on the airstrip at the same time.
According to the Holdridge Life Zone System (Holdridge, 1967), the
Limoncocha area should be classified as Tropical Moist Forest on the
basis of its mean annual temperature (25.20C) and mean total annual rain-
fall (3065 mm). Normally, a dry season (i.e., period with soil moisture
considerably lower than field capacity) of three or four months would be
expected in this life zone with three meters of rain per year. However,
the rainfall distribution pattern at Limoncocha is more even than that
of the zonal climate, resulting in an "atmospheric association" (Holdridge,
1967). The vegetation in this association is, therefore, more luxuriant
than that which would be found in the zonal association (i.e., Tropical
A calculation of water balance (Table 1) shows that, based on an
estimated field capacity of 250 mm, there is an average water surplus
of at least 70 mm every month of the year at Limoncocha. Nevertheless,
there are occasional months dry enough to produce a water deficit. Sig-
nificantly, these have occurred only in the "non-rainy" seasons (Aug.-
Sept. and Dec.-Jan.-Feb.) and are relatively infrequent (see Table 1).
Thus it may be concluded that, except on rare occasions, there is always
sufficient water to maintain the soil's field capacity and that the
Limoncocha forests are therefore not subject to any prolonged or severe
seasonal water deficit.
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Limoncocha is approximately 280 meters above sea level and almost
15 meters above the level of the lake and the two nearby rivers (Rio
Napo and Rio Jiveno). All other relief in the area is less than 10
meters. The soils are mostly laterites, covered in forested areas by
a layer of humus and decaying organic matter several centimeters thick.
Forest soils are always wet and forest trails are muddy year around.
During the wetter periods, water may accumulate in poorly drained areas
to depths ranging from 2 to 70 cm, with standing water remaining any-
where from two days to two months.
The canopy of the mature forest averages 40 to 50 meters in height,
with emergents (e.g., Ceiba) occasionally reaching 70 meters. Undis-
turbed areas have all the characteristic features associated with climax
tropical rain forest: tall, smooth-barked trees with buttressed roots;
abundant epiphytes, creepers, and climbers (lianas); a large saprophyte
community; a relative openness of the forest understory and a correspon-
ding density of the canopy; a monotony of leaf color (dark green) and
leaf form (predominantly elliptical, with an acuminate tip or "drip tip");
a paucity of flowers in the understory; and a high species diversity
(i.e., a great number of plant species present in a small area, each
represented by only a few individuals).
In the Limoncocha forests palms (Palmae) are quite abundant, espe-
cially those known locally as chonta (Iriartea sp.) and chontadura
(Bactris gasipas H.B.K.). Natural clearings, from 0.2 to 1.0 or more
hectares in size, are an unpredictable but not infrequent occurrence
caused by the blow-down of trees. These temporary sunny clearings are
rapidly colonized by various fugitive plant species, especially by mem-
bers of the genera Eupatorium CAsteraceae), Ochroma CBombacaceae),
Heliotropium (Boraginaceae), Cecropia (Moraceae), Heliconia (Musaceae),
and Solanum and Physalis (Solanaceae). These same fugitive elements are
also common along the more open forest trails and along the edges of
In 1974, a total of approximately 83 hectares of land at Limoncocha
had been cleared by S.I.L. and the local Quichuas. This total may be
broken down as follows: airstrip clearing, 20 hectares; missionary set-
tlement, 18 hectares; pasturage, 40 hectares; and Quichua village, 5 hec-
tares (see map, Figure 2). As indicated on the map in Figure 2, there
are several areas of secondary or heavily disturbed forest bordering
the base, totaling approximately 66 hectares. Since 1974, a great many
new clearings have been made along the Napo Road and on both sides of the
Rio Jiveno. By early 1976, virtually all of the remaining lands in these
areas had been claimed by colonistas (James Yost, personal communication),
and thus more clearings can be expected in the future.
The open borders of the grassy airstrip are covered by Ipomoea
(Convolvulaceae) and the exposed forest face by the introduced kudzu
vine (Pueraria lobata). The pasture blends gradually into the surround-
ing disturbed forest. Only a few of the original forest trees are still
standing in the settlement clearing, which has been heavily planted with
fruit trees, including orange, grapefruit, and lemon (Citrus), avocado
(Persea), and banana (Musa), and ornamentals, e.g., African oil palm
(Elaeis guineensis Jacq.) and Hibiscus.
There are several forest trails near Limoncocha. Those used in the
course of this study are described below (also see map, Figure 2).
Napo Road (NR). This is a broad trail, ten meters wide, that runs
south from Limoncocha for three kilometers to the Brazo of the Rio Napo,
at a point just east of the mouth of the Rio Jiveno. Numerous side trails
branch off to the east and west.
Nature Trail (NT). This trail runs west from the Power House for
about 80 meters before it forks into two branches that later reunite to
form a large closed loop. The 80-meter-stem of the NT passes through
second growth forest (see Figure 10). The closed loop occurs in slightly
disturbed primary forest (see Figure 11). This two meter-wide trail has
been marked with numbered stakes corresponding to points of interest which
are explained on a cassette tape (to be played by visitors while walking
the trail). Southeast of the NT loop are a series of anastomosing
trails less than one meter wide which give access to the NT Study Area
Hunting Trail (HT). This trail begins at the western tip of the NT
loop and continues in a broad west-northwest curve. Quite narrow, it is
difficult to follow after the first two kilometers.
Logging Trail (LT). Originally a ten meter-wide trail that would
accommodate a tractor for the first part of its length, this trail angles
NW and roughly parallels the HT. Along it are study sites 1, 2, 3, and
4. In the past, logs were hauled by tractor down this trail to the saw-
mill located in the Power House building. Greatly overgrown today, the
LT fades to less than one meter in width beyond Site 4. A severe storm
with localized twisting winds occurred in March 1974, and blew down
several very large trees and numerous smaller ones between Sites 2 and 3.
The resulting morass of tangled vines, shrubs, and fallen trees rendered
this stretch of the LT nearly impassable. By June 1974, this devastated
trail was so choked with new growth that it was never used again as a
passage to Site 4.
Cross-Cut Logging Trail (CCLT). A five meter-wide trail first cut
in early 1973, this north-south trail links the NT with the LT. After
June. 1974, it provided the quickest means of reaching Site 4. Because
of its width, this trail receives much sunlight and thus is difficult
to keep open. By May 1975, this trail was completely blocked by vines
and Heliconia plants and was no longer passable.
Location of Study sites
Intensive or long-term studies were conducted at six study-site
localities. Site 1, Site 2, Site 3, and Site 4 were located at points
along the Logging Trail. Site 5 and Site 6 were in the Nature Trail
area (see map, Figure 2).
During this study, Sites 1 and 3 were open sunny areas (see Figure
12) with large numbers of blooming Eupatorium plants that attracted many
ithomiines (see Figure 13). Site 2 was a much more shaded spot with
several large Heliotropium plants in bloom. Site 4, bisected by the LT
(see Figure 14), was a one hectare rectangular plot staked out in rela-
tively undisturbed, mature, but seasonally flooded forest (see Figure 15).
Site 5 was a 0.5 hectare plot located in relatively undisturbed, mature,
unflooded forest (similar to that shown in Figure 11). Site 6 was a
transect 100 meters long and 2 meters wide, located along the closed
loop of the Nature Trail (see Figure 11).
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Figure 12. Logging Trail, Study Site 3.
Figure 13. Males of Scada batesi Haensch Feeding at Eupatorium I
Flowers at Study Site 3.
The experiments and observations performed at these study sites
are described in the methods section.
The Butterfly Community at Limoncocha, Ecuador
Along with birds, butterflies are perhaps the most conspicuous of
all neotropical animals. This is primarily the result of their diurnal
habits, the often brilliant coloration of their wings, and their rela-
tive abundance compared to other animal groups in the same region. As
is characteristic of many invertebrate taxa in the tropics (Elton, 1973),
this abundance of butterflies results not from a few common species each
with a large population, but from the presence of a great number of
species most of which have a relatively small number of individuals
(Ebert, 1969). In short, neotropical butterfly communities usually ex-
hibit high species diversity (sensu Simpson, 1949).
The butterfly community of Limoncocha fits this pattern of diver-
sity quite well. In over twelve months of collecting (two collectors)
in the Limoncocha area, about 366 species of butterflies were taken
(this does not include the skippers, Superfamily Hesperioidea, of which
some 75 species were taken). Based on the number of species represented
by only one or two specimens in our collection, I estimate that there
are at least another 75 to 100 species that occur in this area, and pos-
sibly as many as 150 or more. Thus, the total number of butterfly species
at Limoncocha (excluding skippers) is estimated to be between 400 and 500,
with 460 as a reasonable figure.
The reasons for the incomplete sampling are several. First, only
a small portion of the total time spent in the field was devoted to an
active attempt to locate and collect new (i.e., previously untaken)
species. Second, nearly all specimens collected were taken in the lower
four meters of the forest or in and around clearings. Thus, those spe-
cies that fly and perch in the mid to upper forest canopy are quite un-
der-represented in the collection as they were caught only when they
occasionally strayed into the lower levels of the forest or were attracted
to flowering plants in clearings and along trails. Even without the
above restrictions, however, the collection of all species of any insect
group occurring in any one neotropical locality is exceedingly diffi-
cult. Indeed, writing more than one hundred years ago on the low densi-
ty of most insect populations on the upper Rio Solimoes in Brazil,
Bates (1857) concluded that "one year of daily work is scarcely suf-
ficient to get the majority of species in a district of two miles cir-
Third, some species may be present in an area at a given time, then
disappear for a number of months or years, only to reappear at a later
date. In this context, however, "disappear" probably has more than
one meaning. It could mean that a species is always present in an area,
but that its population density becomes so low at certain periods that
its presence could only be detected by the collection of an extremely
large sample. Or it may mean that the species population becomes lo-
cally extinct at times and is re-established only through later immigra-
tion. It is most likely that both meanings of the word describe the
dynamics of some of the species at Limoncocha.
This same phenomenon of periodic occurrence has been observed in
the Limoncocha avifauna. After eight months' study in 1971 and 1972,
David Pearson (1972) compiled a species list of all birds occurring
within a five kilometer radius of Limoncocha. The list numbered 344.
In early 1974 an ornithologist visiting Limoncocha for ten days added
over 30 species to the list. Another ornithologist presently studying
at Limoncocha has now increased Pearson's original list by over 50 spe-
cies. Some of these new birds are undoubtably seasonal migrants that
Pearson might have seen had he been at Limoncocha for a full twelve
month cycle, and some may be species that were present but so rare in
1971 that he never encountered them, but have since become more common.
Still others probably represent species that simply were not present at
the time of Pearson's study but have invaded the Limoncocha area since
Similar phenomena are probably influencing the butterfly community.
Some of the species taken at Limoncocha only once are undoubtably moun-
tain forms that apparently strayed or were blown eastward from higher
elevations on the eastern slopes of the Andes (e.g., Athyrtis mechanitis
salvini Srnka). Also, during short trips to Limoncocha in 1972 and 1973,
I have taken a few species that I never saw or collected again during
the whole of 1974. Furthermore, some species at Limoncocha (e.g., Heli-
copis interrupta) have been observed to occur in "blooms," synchronous
emergences of large numbers of individuals at seemingly unrelated times
of the year, probably triggered by some unique combination of climatic
factors. Heinz Ebert (1969), after years of studies on the frequencies
and distributions of butterfly populations in Brazil, concluded that
many species of butterflies, especially those of the most numerous fam-
ilies (Hesperiidae, Lycaenidae, and Riodinidae), have populations that
are small in size, dispersed widely, and which are not constant in lo-
cality, but "migrate" continuously within a great area of favorable
habitat, such that local colonies are continually appearing and disap-
Thus, just as the scattered distribution of rain forest trees resem-
bles a spatial mosaic (Richards, 1964), so do the temporal vagarities
of butterfly abundance resemble a phenological mosaic. Such variability
in species composition must always be carefully considered when conduc-
ting or evaluating research on tropical butterflies or other insects,
and perhaps even birds and mammals. (This phenomenon has long been rec-
ognized as characteristic of most tropical forest human populations.)
Ross (1967) has observed that the systematics of the Lepidoptera,
especially tropical forms, is in a relatively unstable state. While
he was referring primarily to the generic level and below, it is also
true that very few students of butterflies agree fully on the number and
content of butterfly families. Ehrlich (1958) has published the most
recent comprehensive review of the phylogeny and higher classification
of the Papilionoidea (i.e., butterflies other than skippers), based on
a comparison of a large number of morphological characters. In that
paper he recognized only five families of butterflies, the Papilionidae,
Pieridae, Nymphalidae, Libytheidae, and Lycaenidae. Several long-stand-
ing families were downgraded to the level of subfamily or tribe, in-
cluding the family Ithomiidae. In spite of this, however, many subsequent
workers, especially those who have monographed family-level taxa (e.g.,
Miller, 1968), have rejected much of this downgrading and have chosen
to retain most of the families familiar to lepidopterists. Following
the latter approach in this paper, I recognize nine families of butter-
flies: the Papilionidae, Pieridae, and Libytheidae, plus four families
formed by the separation of Ehrlich's Nymphalidae into the Ithomiidae,
Danaidae, Satyridae, and Nymphalidae, and two from the separation of
his Lycaenidae into the Riodinidae and Lycaenidae. The number of spe-
cies collected at Limoncocha in each of these nine families and
in the Hesperioidea (skippers) is presented in Figure 16. The number
of species estimated to be present in each family (see discussion above)
is also indicated in the same figure.
Unfortunately, there are few published summaries of comparable data
from other tropical forest localities. Most such faunal lists have been
regional in scope, and thus cover a variety of habitat types and a sub-
stantial altitudinal range. To provide a rough comparison, however,
data from three Brazilian sites have been graphed in Figures 17, 18, and
19. Figures 17 (Eastern Espirito Santo and Southern Bahia; Brown, 1972)
and 18 (Eastern Pernambuco; Ebert, 1969) represent regional totals for
two areas located in the isolated strip of littoral forest along Brazil's
southeastern coast. Figure 19 (Jaru, Rondonia; Brown, 1976b) represents
a specific locality in the southwestern Amazonian forest of Brazil.
In general the littoral forests of southeastern Brazil are not so
rich in species as are the lowland forests of the Amazon Basin. Indeed,
the estimated number of species at the single locality of Limoncocha is
greater than that recorded for the entire eastern portion of Pernambuco
(Figure 18) and the single locality of Jaru (Figure 19) is estimated to
have about the same number of species as do the extensive coastal forests
of southern Bahia and Espirito Santo (Figure 17).
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Interestingly, the butterfly faunas of two coastal regions have a
much greater percentage of Hesperioidea (32-36%) than do the Amazonian
forest areas (25-26%). The presence of extensive grassland and cerrado
areas in the coastal regions probably account for the greater relative
number of skipper species in these areas; many skippers specialize on
A comparison of the two Amazonian forest localities reveals that
the distribution of species among families is quite similar at Limon-
cocha (Figure 16) and Jaru (Figure 19), although the overall species
richness of the Jaru site may be exceptional (with many years of field
experience across South America, Brown, 1976b, has called it "...the
most exceptional collecting area I have ever seen or imagined"). Thus,
I conclude that Amazonian lowland forests may be characterized by a
relative distribution of butterfly species among families similar to
that shared by Limoncocha and Jaru. The families may be ranked accord-
ing to the number of species they contain. Beginning with largest, the
order is (1) Hesperiidae (Hesperioidea), (2 and 3) Riodinidae and Nym-
phalidae (very nearly equal, but either family may outnumber the other
at a given locality), (4) Lycaenidae, (5) Satyridae, (6) Ithomiidae,
(7) Pieridae, (8) Papilionidae, (9) Danaidae, and (10) Libytheidae. The
actual number of species present in each family at most lowland Amazonian
sites probably varies roughly between the values given for the number of
species actually caught at Limoncocha (Figure 16) and the number estimated
to occur at Jaru (Figure 19).
A comparison of butterfly faunal lists from various areas in the
Neotropics (Table 2) suggests that the Ithomiidae form from 4.5 to 12%
of the number of species of Papilionoidea present in a given area.
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Samples from predominantly forested areas, the preferred habitat of
ithomiines, have a higher percentage of Ithomiidae than do samples which
include cerrado or grasslands. Likewise, the western and southern Ama-
zonian forest areas have the highest percentages of ithomiines, no doubt
because these areas, which correspond to the Napo and Rondonia Refuges
(Brown, 1976a), were principal centers of geohistorical evolution in the
subfamily (Brown, 1972).
The above discussion considers only the number of species present
in a given area, and says nothing of the numbers of individuals. Unfor-
tunately, estimates of absolute population size of neotropical butterfly
populations in tropical forest areas are practically non-existent. The
low density of most species' populations limits the use of the insect
ecologist's favorite technique, the capture-mark-recapture sampling se-
ries. Until alternative techniques of population size estimation are
available, we must be content with estimates of relative abundance, al-
though these are usually severely biased by the investigator's collecting
technique, preference for certain taxa, and a tendency to concentrate on
unusual or showy species. While techniques to determine the number of
butterfly species present in tropical areas have been recently refined
(Brown, 1972), little attention has been given to the estimation of abso-
lute population sizes of tropical insects (but see Elton, 1973).
Although all of the species of butterflies which occur at Limon-
cocha are, by definition, inhabitants of lowland tropical rainforest,
they differ widely in their preferred microhabitats. Species which are
characteristically found in open fields, and along roads and rivers may
be called campestral, while those found predominantly in the forest can
be termed sylvestral. Some species are sun-loving (heliophilic), others
are shade-loving (scotophilic). Various levels within mature forest,
from the lower understory to the upper canopy, contain different, though
overlapping, groupings of species.
Of concern to the present work are those species which share the
same microhabitats with members of the Ithomiidae, and especially those
involved in mimetic relationships with ithomiines. The characteristic
habitat, or referendum, of each butterfly family at Limoncocha may be
briefly summarized as follows (all Limoncocha ithomiines and many mimetic
species of other families are illustrated in Figures 58-65).
Papilionidae. Most of the larger non-mimetic species are helio-
philic, usually flying above the canopy, and thus are most often seen in
clearings and along open trails (Papilio) or rivers (Graphium). Mimetic
species (Parides, Battus) appear to be rarer in number and are usually
found in the mid to upper levels of the forest or along shaded trails.
Pieridae. Most of the Pierinae (except the mimetic genera Archonias,
Itaballia, and Perrhybris) and the Coliadinae (except for the fragile
Leucidea brephos) are heliophilic and campestral, commonly flying along
rivers and open trails or in clearings. The mimetic genera of the
Pierinae are chiefly sylvestral, but often wander along the edges of
clearings or shaded trails. The six Limoncocha species of Dismorphinae
are all mimetic and rarely stray from the forest interior. D. pinthaeus,
D. theugenis, D. erythroe, and D. leuconoe are restricted to the lower
levels of the understory, while D. orise and D. amphione frequent the
mid and upper canopy, respectively.
Ithomiidae. Most species are scotophilic and tightly restricted to
the forest understory, although a few are found in the upper levels of
the forest. Members of a few genera frequent the sunny edges of clear-
ings (e.g., Ceratinia, Mechanicis) while others (e.g., Melinaea, Tithorea)
often fly in the sunlit upper canopy.
Danaidae. The monarch, Danaus plexippus, is campestral, especially
common over pastures and large clearings. The mimetic Lycorea ceres is
sylvestral and heliophilic, visiting flowers of the upper canopy and
forest edges. The clearing mimic, Ituna lamirus, is a deep forest
Satyridae. Most species are dark and cryptic in coloration, scoco-
philic, and occupy only the lower levels of deep forest understory, al-
though some Euptychia are found in second growth or grassy areas as well.
The Brassolinae are crepuscular, often flying in banana groves or along
open trails. Mimicry is rare.
Nymphalidae. This large family is quite diverse both morphologically
and behaviorally. Although most non-mimetic species are heliophilic to
some extent and are often found in the sunlit upper canopy, along open
trails and rivers, and in clearings, others, e.g. Nessaea regina, are
sylvestral. Batesian mimics usually occupy the same microhabitats as
their models, e.g., Phyciodes actinote is found in the forest interior,
and Anaea (Consul) fabius is found in the upper canopy.
Lycaenidae. This is a large family of generally quite small butter-
flies, most of which are sylvestral, frequenting sunlit patches in the
mid to upper levels of deep forest. Many species are rare, difficult to
see, and harder to catch. Mimicry is uncommon.
Riodinidae. Another family of generally small butterflies,
the metalmarks are quite similar ecologically to the Lycaenidae. Mimi-
cry is not uncommon, but the mimetic relationships are for the most part
poorly understood as they rarely involve classical models. Both species
richness and heterogeneity of the Riodinidae is higher than that of the
Lycaenidae at Limoncocha, and the range of wing coloration and patterning
Hesperiidae (Hesperioidea). In temperate areas skippers are charac-
teristically campestral, associated with open fields and second growth
areas, but in the tropics there are a great many sylvestral species.
Some are brightly colored blue or red, but most are of a yellow, brown,
or dull orange. Mimicry is rare.
The mimetic associations present at Limoncocha, with special ref-
erence to the Ithomiinae, will be discussed in Chapter 7.
The Butterfly Subfamily Ithomiinae
The Ithomiinae have been, and are, largely neglected
by students of Exotic Lepidoptera, and one hears as the
reason that they are less beautiful than other groups and
more difficult. The first answer I will ask you to dismiss
from your minds, for it cannot be a well-considered state-
ment by any who make it. As for the latter--the one of
difficulty--there is certainly more truth in it, but it is
not nearly so great as is often averred, and what difficulty
there is should stimulate us to fresh endeavours to over-
--W. J. Kaye (1914)
The stimulation to fresh endeavours has been long in coming.
During the first fifty years after Professor Kaye delivered his challenge
before a meeting of the South London Entomological and Natural History
Society in 1913, the Ithomiinae were all but ignored except by a very
few workers, mostly taxonomists. Only in the last ten years, and par-
ticularly in the first half of the present decade, have ecological and
behavioral studies been attempted. Since ithomiines are among the most
numerous and conspicuous animals in a rapidly disappearing biome, the
neotropical rainforest, such attention is long overdue.
The butterfly family Ithomiidae comprises two geographically dis-
junct subfamilies, the Tellervinae and the Ithomiinae. Containing only
the single monotypic genus Tellervo, the Tellervinae are restricted to
the insular belt of tropical forests from the Cape York peninsula of
Australia north through New Guinea and the Bismark Archipelago, west to
Celebes, and east to the Soloman Islands (Common and Waterhouse, 1972).
The Ithomiinae are entirely neotropical, ranging from sea level to 3000
meters elevation in the tropical and subtropical portions of Central
and South America. Only two species occur in the Antilles, one on Cuba
and another on Jamaica and Hispanola (Fox, 1963).
The Ithomiinae have had a nomadic taxonomic history (reviewed in
Fox, 1956). Over the past two hundred years they have been shuffled
among various family groups, including the Heliconiidae, Nymphalidae,
and Danaidae. For most of this century both the Ithomiinae and Teller-
vinae have been considered part of the Danaidae because that was the
arrangement in Seitz's widely distributed The Macrolepidoptera of the
World (Seitz, 1924). After considerable morphological and systematic
study, Fox (1949, 1956) concluded that the Ithomiidae were worthy of
familial rank and called into question their classical association with
the Danaidae. He considered the Ithomiidae to be primitive among the
Nymphaloidea, and most closely related to the Satyridae. Gilbert and
Ehrlich (1970), however, have reviewed the evidence of the larval, pupal
and adult morphology, the foodplant relationships, and the behavioral
characteristics of the Ithomiidae and Danaidae and concluded that the
two share a much closer relationship than do the Ithomiidae and the
Satyridae. Data collected in this study provide further evidence in
support of the Ithomiidae-Danaidae relationship.
Since the classic work of Richard Haensch (1903, 1905, 1909), the
most active students of the Ithomiinae have'been R. Ferreira d'Almeida
(see Brown, F., 1975, for a complete bibliography) in Brazil and W. T.
M. Forbes (see Fox, 1956, for bibliography) and Richard M. Fox (see
Brown, F., 1968, for a complete bibliography) in the United States. Fox
began a monographic revision at the family level which was uncompleted
at the time of his death in 1968. Of the eight tribes he recognized in
the Ithomiinae (Fox, 1949), he completed the revisions of only the first
four: Tithoreini (Fox, 1956), Melinaeini (Fox, 1960), Mechanitini (Fox,
1967) and Napeogenini (Fox and Real, 1971). Gerardo Lamas M. (1973)
and Herman Real (personal communication) are presently working on the
taxonomy of selected genera of the four remaining tribes (Ithomiini,
Oleriini, Dircenini, and Godyridini).
The numbers of genera and species contained in the Ithomiinae are
far from being decided with certainty. The recent trend in the evolu-
tion of the taxonomic study of this subfamily has been a reduction in
the number of recognized species. As the biological relationships of
many allopatric forms become better known, many of these forms are com-
bined to form wide-ranging, polytypic species, some with a great many
named subspecies. Simultaneously with the reduction in the number of
species recognized, there has been a gradual increase in the number of
recognized genera as the morphological relationships of greater numbers
of species began to be more closely studied. For example, Haensch (1909*),
in Seitz's The Macrolepidoptera of the World, listed 883 named forms,
most of them treated by him as species, occurring among 33 genera. Since
that time the number of recognized genera has been increased by about
one-third and the number of recognized species reduced by about one-half.
Presently, there are 49 genera recognized in the Ithomiinae and, in
spite of the steady stream of descriptions of new species of ithomiines
over the past five decades, the number of valid species is probably only
In Table 3, the eight tribes of the Ithomiinae are listed, and the
number of genera and species estimated to occur in each are presented.
This table was prepared from the list of genera assigned to each tribe
by Fox (1956), modified by the subsequent description of new genera in
the subfamily (Fox, 1967; Fox and Real, 1971; Brown and d'Almeida, 1970;
Brown et al., 1970; Lamas M., 1973). The numbers of species in the first
four tribes are taken from Fox's Monograph. The numbers of species in
the remaining four tribes were roughly estimated by applying a formula
of reduction to the number of forms listed by Haensch (1909). The
* Although Volume V, The American Rhopalocera, of A. Seitz's The Macro-
lepidoptera of the World was not published as a unit until 1924, various
sections of this work were issued earlier as fascicles. The section on
the Danaidae, which included the Ithomiinae, was written by R. Haensch
and was first published in 1909.
Table 3. The Number of Genera and Species in the Eight Tribes of the
Number of Number of Number of Ratio
Genera Species* Named Forms Forms/Species
Tithoreini 8 18 63 3.5
Melinaeini 1 17 55 3.2
Mechanitini 6 34 76 2.2
Napeogenini 7 104 236 2.3
Ithomiini 3 (28) 64 (2.3)
Oleriini 4 (51) 117 (2.3)
Dircennini 9 (139) 320 (2.3)
Godyridini 11 (54) 125 (2.3)
Totals 49 (445) 1056
Source: Data for number of genera from Fox, 1956; Fox, 1967; Fox and
Real, 1971; Brown and d'Almeida, 1970; Brown et al., 1970;
Lamas M., 1973.
Data for number of species in tribes Tithoreini, Melinaeini,
Mechanitini, and Napeogenini from Fox, 1956, 1960, 1967;
Fox and Real, 1971.
Data for number of species in the Ithomiini, Oleriini, Dir-
cennini, and Godyridini from Haensch, 1909.
Note: See discussion in text.
* Numbers in parentheses are estimates.
formula was derived as follows. As treated by Fox (1967) the Mechanitini
contain 76 named forms divided among 34 species, and the Napeogenini
(Fox and Real, 1971) contain 236 named forms divided among 104 species.
The ratio of forms to species for the two tribes is thus 2.2 and 2.3
respectively. Applying the figure 2.3 to the number of forms given by
Haensch (1909) for each of the four tribes not treated by Fox, we arrive
at an approximate number of species per tribe. (The ratios for the
Tithoreini and Melinaeini are 3.5 and 3.2, but both of these tribes
contain relatively primitive genera, each with a relatively few, wide-
spread, polytypic species. The ratios of the Mechanitini and the Napeo-
genini are more applicable for comparisons to the remaining four tribes.)
This gives a total number of species for the Ithomiinae of approximately
445. Thus, the 53 species at Limoncocha represent a little more than
10% of the total number of ithomiine species, but only about 5% of the
total number of named forms (which probably exceeds 1100 today). Of the
49 genera in the subfamily, 24 are represented by species occurring at
Morphologically, members of the Ithomiinae may be characterized
as follows. Adults are generally medium-sized butterflies, although
wingspan within the subfamily varies from less than 3 cm to over 10 cm.
The forewings are generally long and narrow, but not quite so pronounced
in these characteristics as are the wings of the Heliconiinae. Wings
may be either opaque (usually some combination of black, brown, orange
or yellow) or translucent or transparent, in which case the wing scales
are reduced to tiny hairs in the clear areas. Antennae are long (be-
tween one half and two-thirds the length of the forewing) and thin,.with
a slender, unsealed club. The abdomen is quite long and slender, pro-
jecting well beyond the anal margin of the hindwing. All males possess
an androconial scent patch located on the dorsal costal margin of the
hindwing. The scent patch is accompanied by an androconial brush con-
sisting of a cluster of hair-like scales attached along the posterior mar-
gin of the scent patch. Both the scent patch and the androconial brush
are normally covered by the overlapping forewing. The androconial scent
patch and brush primitively extend the length of the discal cell. They
may be separated, however, into a distal portion and a proximal portion
so that some species have two androconial patches. Either the distal
or proximal androconia may be absent in other species. This costal
scent patch is diagnostic of the Ithomiinae (it is not present in the
Tellervinae) and, because of its variation, is a useful taxonomic charac-
ter at the generic level. With the exception of the genus Thyridia, fe-
males of the Ithomiinae do not have the androconial patch and brush.
The neuration of the hindwing, another generically useful taxonomic
character, is nearly always different in the sexes, often markedly so.
A discussion of the ecological requirements and characteristics of
the adults, and descriptions of the early stages of the Ithomiinae will
be presented in Chapters 3 and 5, respectively.
A list of the 53 species of Ithomiinae collected at Limoncocha dur-
ing this study is presented in Table 4. The species are arranged by
tribe and a subjective estimate of the relative abundance of each at
Limoncocha (based on thirteen months' observations) is given in the table.
The number of species occurring in each of the five categories of abun-
dance is presented graphically in Figure 20. It is obvious from this
graph that the majority of species at Limoncocha are uncommon or rare.
In fact, only about 40% of the species are abundant or common. About
15% of the species are very rare (i.e., no more than 5 specimens were
collected in 13 months) which suggests that, in an ecological sense,
the effective number of species at Limoncocha may be somewhat less than
53. For example, a single male of Oleria tigilla was collected
during a three week visit to Limoncocha in September 1972. This'species
was therefore expected during the 1973-1974 study period, but, in
fact, not a single Limoncocha specimen was taken during this time.
During the course of this study it was possible to make a few brief
collecting trips to other lowland forest areas in the Oriente. One-
day collections were made at Dureno (275 m), on the Rio Aguarico, and
at Veracruz (900 m), just east of Puyo, and several days were spent
at Shell (1065 m), on the Rio Pastaza, and at Tiwaeno (410 m), on the
Rio Tiwaeno (see map, Figure 1). These supplementary collections re-
vealed that several of the species that fall into the "very rare"
category at Limoncocha are much more common in other areas of eastern
Ecuador (e.g., Oleria tigillawas found at both Dureno and Tiwaeno).
Such species are so indicated in Table 4. Thus it may be concluded
that Limoncocha occurs at, or just beyond, the normal distribution
of these species at this time. It must be remembered, however, that
such species may have been breeding residents of the Limoncocha area
in the past, and may be so again in the future (see discussion in
previous section of this chapter).
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CATEGORY OF ABUNDANCE
Relative Abundances of Species of Ithomiinae
at Limoncocha, Ecuador.
A = Abundant
C = Common
U = Uncommon
R = Rare
VR = Very rare
The Plant Family Solanaceae
The Solanaceae, or nightshade family, comprises some 80 genera of
diverse form (D'Arcy, 1973) and contains approximately 2300 species
(Cronquist, 1968). Although the family is strongly centered in tropical
America, there are many species of a few genera in Africa, several iso-
lated genera in Australia, and at least a few species in most parts of
the world. Endemism is greatest in South America, where there are 38
endemic genera (Lawrence, 1951), of which 14 occur in the temperate
portion (D'Arcy, 1973). The Solanaceae have long been included in the
Tubiflorae, a large order of some 25 families containing a great number
of species (Cronquist, 1968). Recent taxonomists usually subdivide this
unwieldy taxon into three orders, the Polemoniales, the Lamiales, and
the Scrophulariales. Depending on the cut of the taxonomist's knife,
the Solanaceae are usually included in the Polemoniales (Lawrence, 1951;
Cronquist, 1968) or the Scrophulariales (Takhtajan, 1969).
Floras treating the Solanaceae of tropical America have been pub-
lished for most of Central America, including Costa Rica (Standley and
Morton, 1937), Guatemala (Gentry and Standley, 1974), and Panama (D'Arcy,
1973), but only one country in South America, Peru (MacBride, 1962;
Correll, 1967), has been so treated. Unfortunately there is no Flora
of Ecuador, the site of my research, and thus I have used the publications
of D'Arcy (1973) and MacBride (1962) to arrive at generic determinations
in the field. Dr. D'Arcy has been kind enough to supply the specific
determinations of the Ecuadorian solanaceous specimens I have sent to
him. There exist a few publications containing information on some of
the cultivated species of Solanaceae from the Andean slopes of Columbia,
Ecuador, and Peru, most notably Lawrence (1960), Schultes and Romero-
Castaneda (1962), Patino (1962), Jimenez (1966), Pacheco and Jimenez
(1968), and Heiser (1968a, b, 1971). D'Arcy (1974) provides a
bibliography of some of the more recent literature on Neotropical
The family is quite diverse morphologically, and includes herbs,
shrubs, trees, lianas, and epiphytes. The trunks, petioles, and midribs
of Solanaceous plants are often armed with acicular (needle-like) or
recurved (hook-like) spines, the latter type being especially common
on lianous forms. The leaves may be glabrous but more often are pubes-
cent with simple, dendritic, stellate, scutellate, and/or glandular
hairs. Stellate hairs in particular are well developed in the family
and quite diverse in form. Some species have tough, coriaceous (leathery)
leaves while others have leaves with a waxy cuticle. In short, the
family employs a variety of mechanical defenses against herbivory that
are developed to a greater or lesser degree among the various genera and
species. In addition, secondary plant substances in the form of alkaloids
are widely distributed in the Solanaceae (Henry, 1949; Raffauf, 1970;
Willaman and Schubert, 1961) and there has been increasing recognition
of their possible role as a chemical line of defense against herbivory
(Fraenkel, 1959; Ehrlich and Raven, 1964).
Many members of the Solanaceae are of considerable economic impor-
tance to man. Indeed, Uphof (1968) lists 92 speceis from 21 genera as
possessing value as agricultural crops, as sources of pharmaceutical
chemicals, or as ornamental plants. The fascinating history of man's
encounters with many of these plants has been delightfully related by
Charles Heiser (1969). Agricultural crops include the common tomato
(Lycopersicon esculentum), the cultivated and Andean potatoes (Solanum
tuberosum), peppers (Capsicum, several species), tree-tomato (Cyphomandra
crassicaulis), naranjilla or lulo (Solanum quitodnse), and eggplant
(Solanum melongena), to name a few. Approximately 151 different alkaloids
had been isolated from solanaceous plants by 1968 (Raffauf, 1970), many
of which have strong narcotic or other physiological properties. Accord-
ingly, a number of solanaceous plants and their alkaloids have medicinal
value and thus are economically important to the pharmaceutical industry.
For example, belladonna (Atropa belladona) and Jimsen weed (Datura stra-
monium) contain the alkaloids atropine and scopolamine, respectively.
Other drug-producing solanaceous plants are grown for non-medicinal pur-
poses, e.g., the various species of tobacco (Nicotiana) which are
important cash crops in many parts of the world. Ornamentals come from
many genera in the Solanaceae, especially Petunia, Salpiglossis,
Schizanthus, Lycium, Solanum, Streptosolen, Cestrum, Datura, Solandra,
Browallia, Nierembergia, and Brunfelsia (Lawrence, 1951).
Of interest to the present study is the fact that nearly all reported
foodplants of the larvae of neotropical ithomiine butterflies (Ithomiinae)
are in the Solanaceae. This familial-level correlation between the
Ithomiinae and the Solanaceae, and the concomitant phytochemical ecol-
ogy of alkaloid metabolism, have implications to insect-plant coevo-
lucion that will be discussed in Chapter 6. With the addition of the
information contained in the present study, the number of solanaceous
genera on which ithomiine larvae have been reported to feed is raised
to eleven. These eleven genera can be briefly characterized as follows
(information from D'Arcy, 1973, and Uphof, 1968, unless otherwise noted).
Brunfelsia. This is a tropical American genus of 25-30 non-
herbacious species, mostly shrubs, with leaves simple, entire, coriaceous
to chartaceous, and often glabrate. Several species, e.g., B. calycina
var. floribunda, are widely cultivated as ornamentals. In Spanish they
are usually known as "galan de noche." The Manaca Raintree, B. hopeana,
contains the very poisonous alkaloid manacine, which resembles strychnine
in physiological effect. In Brazil, the dried root of this plant is
used in the treatment of rheumatism and syphilis.
Capsicum. The pepper genus contains perhaps a dozen species, most
of which (and especially C. annuum and C. frutescens) are cultivated
throughout the world for their culinary and ornamental fruits. Peppers
are annual or short-lived perennial herbs, with leaves simple, entire
or weakly toothed, glabrous or pubescent with simple, sometimes glandular
Cestrum. This is a tropical American genus containing 150-250
species of unarmed shrubs or trees, with leaves simple, entire, mostly
glabrous above and variously pubescent beneath, usually with simple or
dendritic hairs. Several species are widely cultivated as ornamentals,
and a few are used for medicinal purposes on a local basis. One species,
C. lanatum, is placed in hens' nests by Mexicans to keep away parasitic
Cyphomandra. Occurring mainly in montane South America, Cypho-
mandra contains about 50-60 species, some of which are used by man for
food. The plants are unarmed shrubs, trees, or vines, leaves simple
or compound, entire or lobed, usually glabrous above and pubescent or
puberulent below. The tree tomato, C. crassicaulis (=C. betacea), has
been cultivated for centuries by Peruvian Indians, and is presently
grown for its edible fruit in Australia, New Zealand, and in some parts
of South America. C. hartwegii is occasionally cultivated for its
edible fruit in Chile, Argentina, Colombia, and Panama, and is known
in the latter country as "contra gallinazo" (against chicken-heartedness).
Datura. This infamous genus contains about ten species of unarmed,
ephemeral or perennial herbs or shrubs, sometimes with woody trunks,
occasionally fetid, leaves simple and entire, repand or variously pin-
nately lobed or toothed, pubescent with mostly simple, sometimes viscid,
hairs. Species of Datura are found in warm temperature regions in both
the New and Old Worlds, but Mexico, with eight native species, is prob-
ably the center of speciation. The potent alkaloids found in this genus,
such as atropine, hyoscyamine, and scopolamine, impart to these plants
a variety of drug-related uses, ranging from the treatment of asthma to
criminal poisoning. Alkaloids occur in several parts of the plants, but
especially in the seeds and leaves.
Juanulloa. This is a little-known genus of about ten species of
unarmed shrubs, mostly growing as hemi-epiphytes high in the forest
canopy. The leaves are simple, entire, and glabrous to tomentose with
dendritic hairs. A few species are cultivated as novelties in temperate
Lycianthes. Closely related to Solanum and often confused with it,
Lycianthes contains about 200 species, mostly from tropical America.
The genus includes herbs, shrubs, and vines, usually unarmed, the leaves
simple, entire or nearly so, glabrous or pubescent with various types
of hairs. One or two species are occasionally grown as ornamentals.
Lycopersicon. Also closely related to Solanum ;Lycopersicon is
a genus of six species and several varieties centered in the coastal
region of western South America. The plants are unarmed, sprawling,
ephemeral or perennial herbs with pinnately lobed leaves, pubescent
with glandular, aromatic hairs. The cultivated tomato, L. esculentum,
is an important vegetable crop in many countries.
Physalis. This genus contains about 90 species, with the greatest
number in Mexico, some in Central and South America, and a few in the
Old World. These unarmed plants are mostly herbs, rarely shrubs, with
leaves simple, entire, shallowly toothed or lobed, pubescent with sim-
ple, often glandular or viscid, rarely dendritic hairs. Commonly called
ground cherries, several species are cultivated for their fruits which
are eaten raw or cooked, or made into preserves (e.g., P. ixocarpa).
P. alkekengi is cultivated both as an ornamental and for medicinal
Solanum. Solanum is one of the largest genera in the plant kingdom.
Over 3,500 species have been described, but probably only about 1,400
of these are sound (D'Arcy, 1974). A recent study (D'Arcy, 1972) rec-
ognizes 7 subgenera and 50 sections. The morphological diversity of
this genus is striking, and includes herbs, shrubs, trees, and lianas,
with epiphytic, procumbent, and tuber-bearing species all represented.
Plants may be armed or not, glabrous or pubescent with a variety of
simple, branched, stellate, or peltate hairs, these often glandular,
sometimes accompanied by bristles. Leaves may be simple or compound,
entire, toothed, or variously lobed, sometimes armed. Almost worldwide
in distribution, the genus has its greatest number of species in tropical
America, but is well represented in temperate America and in Africa.
Hybridization and polyploidy are widespread (Heiser, 1969). There are a
great many Solanum species of economic importance to man, including agri-
cultural crops, medicinal plants, ornamentals, and noxious weeds. In
terms of acreage, tonnage production, market value, and dietary impor-
tance, Solanum tuberosum, the cultivated potato, is one of man's most
important dicotyledonous crop plants. Other important food plants in
this genus include the eggplant (S. melongena), cultivated in various
parts of the world, and the lulo, or naranjilla (S. quito6nse), of Colom-
bia and Ecuador. Ornamentals include S. wendlandii, S. seaforthianum,
S. pseudocapsicum, and many others. S. torvum is cultivated in eastern
Europe for its steroid alkaloids. The fruits of S. mammosum and other
members of the section Acanthophora (subgenus Leptostemonum) are used in
Ecuador and elsewhere for killing roaches, exterminating rats (MacBride,
1962), and for a variety of medicinal purposes. They are perhaps poi-
sonous to mammals, but their armament is sufficient to discourage most
Witheringia. This genus has only recently been clarified as a
taxonomic entity (Hunziker, 1969) and includes about 18 species ranging
from Mexico to northern South America and perhaps one species in the
South Seas. These plants are unarmed, erect herbs or subshrubs, with
leaves simple, entire or sinuate, dentate, membranaceous, with simple
or dendritic hairs. They have no known economic importance to man.
The examples given above of local uses of solanaceous plants for
medicinal and insecticidal purposes attest to the potent nature and
widespread occurrence of alkaloids in the family.
During the course of this study, forty-two different plants at
Limoncocha were recognized as belonging to the Solanaceae. There are
undoubtedly many more Solanaceae present in the area, especially trees
and lianas of the upper forest canopy, but recognition of solanaceous
plants not in flower or fruit, especially those occurring in the canopy,
is quite difficult. A list of these forty-two species, along with the
voucher number, estimated abundance, habit, and typical habitat of each
one, is given in Table 5. Although there are eleven genera represented,
nearly two-thirds (64.3%) of the forty-two species are in the genus
Solanum. No other genus has over three species. The eleven genera,
and the number of species in each, are: Brunfelsia (1), Capsicum (2),
Cestrum (2), Cyphomandra (2), Jaltomata (1), Juanulloa (1), Lycianthes
(2-3), Lycopersicon (1), Physalis (2), Solanum (27), Witheringia (1).
Grouped by growth form, the Limoncocha species include eighteen
herbs, fourteen shrubs, two trees, and eight lianas. Two of the lianas
are epiphytic. In regard to habitat, nineteen species are characteris-
tically found in primary forest and an equal number are characteristically
associated with disturbed areas or secondary growth. Four species are
entirely domestic. Grouped according to light tolerance, nineteen are
found growing in full or partial sun, fourteen occur in areas of open
shade, and only nine are found in deeply shaded areas of the forest
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Field work at Limoncocha, Ecuador, was conducted from November
1973 to November 1974. Aerial insect nets (American Biological Supply,
Baltimore, Maryland) of 18-inch diameter and with standard (3 feet) or
adjustable (2 to 12 feet) handles were used for collecting. Captured
butterflies were placed in glassine envelopes carried in a small tin
attached to the collector's belt. If they were to be released later in
capture-mark-recapture experiments, kept for oviposition experiments, or
used for dissections, the butterflies were left alive; otherwise, they
were killed with a firm pinch at the thorax.
At the beginning of the study a large reference collection of
ithomiines and other butterflies was made, and the ithomiines were deter-
mined to genus using the key in Fox's (1940) "Generic Review of the
Ithomiinae." Each species was given a voucher number and a reference
file was maintained so that collected individuals could be readily iden-
tified. Nevertheless, the superficial similarity of most Ithomiinae
made field identification of the many Limoncocha species difficult.
Therefore, a "field guide" or reference notebook was prepared by sealing
butterfly wings between sheets of plastic laminate (Full-vu Laminating
Film, Cook's Inc., Blackwood, N.J.). For each species of ithomiine, and
for each mimicking species of butterfly or diurnal moth, the left forewing,
hindwing, and antenna were sealed together with a label to provide ,a
ready means of comparative identification in the field. The "field guide"
worked well and, because it was waterproof, held up admirably throughout
the study. After about three or four months of experience in the field
it was possible to identify nearly all perched individuals, and most of
those in flight, to species without the aid of the field guide. Later in
the study the Limoncocha Ithomiinae were determined to species and sub-
species by using the keys in Fox's "Monograph of the Ithomiidae" (1956,
1960, 1967, and Fox and Real, 1971) and by comparison with labelled mate-
rial in the Allyn Museum of Entomology in Sarasota, Florida.
To establish associations between ithomiine species and their food-
plants, female butterflies engaged in apparent foodplant searching behav-
ior were followed. If an ithomiine was observed ovipositing, the eggs
and the female were brought back to the laboratory for culturing. In
addition, plants recognized as solanaceous were thoroughly searched for
eggs or larvae, and any immature stages found were collected for cultur-
ing. Once foodplant relationships were known or suspected, an attempt
was made to induce oviposition by confining a female ithomiine in a
screened cage with an appropriate plant or plants. Screened cages of
small (15x15x30 cm), medium (50x50xl20 cm), and large (3.7x3.7x1.8 m)
size were used for these experiments but none provided very satisfactory
Early stages of ithomiines were cultured as follows. Each collec-
tion of immature stages (set of eggs or larvae from the same female par-
ent) was given a brood number and placed, along with the leaf on which
it was found, in an expanded plastic bag (volume approximately 1500 cc).
The bags were kept in the laboratory (one room of a small two-room
house of wood frame with large screened windows) where lighting and
temperature were similar to the forest understory. After hatching, the
larvae were fed as often as necessary (usually once a day) with field-
collected leaves from the appropriate foodplant. At the time of feeding,
old leaf material and frass were discarded and parasitized or moribund
larvae were separated from the rest of the brood. Records of each brood
were kept in bound notebooks. Data collected daily included the lateral
width of the head capsule (measured to the nearest tenth of a millimeter
with a calibrated ocular micrometer in a Bausch and Lomb binocular micro-
scope), the length of the body (measured to the nearest half millimeter
with a ruler), the occurrence of ecdysis (verified by the collection of
the shed head capsules), and a description of the color and patterning
of the integument. Observations on larval feeding and resting behavior
were recorded and close-up photographs (using a Pentax 35 mm single lens
reflex camera with macro lens and electronic flash) were made of the
early stages of most of the species reared.
Cast larval head capsules and pupal cases were preserved dry in la-
belled pillboxes. Depending on the availability of larval material, an
attempt was made to preserve an individual of each larval stadium of
each species. Larvae were killed and fixed for 24 hours in a solution
of nine parts ethyl alcohol to one part acetic acid. After fixing the
larvae were stored in stoppered vials of 95% alcohol. Adults reared in
the laboratory were preserved dry in glassine envelopes marked with the
appropriate brood number. All preserved specimens are in the author's
Solanaceous plants were tentatively identified to genus with the
aid of the keys in MacBride (1962) and D'Arcy (1973) and each species
was assigned a voucher number for reference. Representative plants of
each species were labelled in the field with the voucher number written
on surveyors' tape. Specimens, in flower or fruit if possible, were col-
lected and pressed for future identification by Dr. William D'Arcy. The
identified specimens have been deposited in the Missouri Botanical Garden,
St. Louis, Missouri. The author has retained a duplicate series for
Surveys were conducted in four different forest areas to determine
the number of individuals of each solanaceous species present. The
height and number of leaves of each solanaceous plant were recorded.
Each plant was carefully searched for-ithomiine eggs, larvae, and pupae.
The four areas searched were (1) the east half (.25 hectares) of the 0.5
hectare plot at Site 4, (2) the .25 hectare plot at Site 5, (3) a 100 m
by 2 m transect along the Nature Trail under closed canopy (Site 6) and
(4) a 100 m by 2 m transect along the Logging Trail under open canopy
Behavioral observations on courtship, copulation, oviposition, feed-
ing, etc., were recorded directly into field notebooks. All times of day
reported here are Eastern Standard Time. Lack of funding thwarted plans
for recording behavioral sequences on 8 mm movie film. Instead, notes,
drawings and 35 mm photographs were taken to document ithomiine behaviors.
Binoculars were occasionally useful for observing high-flying species. A
Bacharach sling psychrometer (Bacharach Instrument Co., Pittsburgh, Pa.)
held one meter above the ground was used to record forest temperatures
and relative humidities.
All capture-mark-recapture experiments employed the marking technique
of Ehrlich and Davidson (1960) so that every collected individual re-
ceived a different number. Marks were made on the wings with "Sharpie"
indelible pens (Sanford Corp., Bellward, Ill.) of various colors, depending
on the background color of the wing pattern. At the time of marking, each
butterfly was handled with stamp-tong style forceps and the following data
were recorded: sex, wing condition, number (if previously marked), and
forewing length. Any information written on the glassine envelope at
the time of collection was also recorded in the record book. Wing condi-
tion was scored on the basis of progressive scale loss to provide an es-
timate of relative age of the butterfly. Seven categories of scale loss
were recognized: F+ generall or immaculately fresh), F (fresh, no scale
loss), F- (almost fresh, some scale loss), I (intermediate scale loss),
I- (heavy scale loss, but no fraying of wing margins), W (heavy scale
loss, some fraying of wing margins), and W- (heavy scale loss, with tat-
tered and/or stained wings). Wing tears and beak marks are not reliable
indicators of age since they may occur at any time during the life of a
butterfly and thus were not incorporated in the measurement of wing condi-
tion. Forewing length was measured with a ruler to the nearest 0.5 mm
from the base of the left forewing (articulation with thorax) to the
most distal point on the wing tip.
The capture-mark-recapture experiments in the forest areas (Sites 4
and 5) were conducted by systematically covering the study plots for one
hour, collecting all ithomiines and other mimetic Lepidoptera encountered.
Individuals seen but not collected (out-of-reach, missed swings of the net,
etc.) never exceeded three percent of the total number collected. At the
end of the hour's collecting, all specimens were marked and released.
The 0.5 hectare study plot at Site 4 was subdivided into fifty sub-
plots, each marked with a numbered stake in the southwest corner. The
number of the plot in which a butterfly was caught was recorded on its
glassine envelope and transferred at the end of the hour (during
marking) to the record book. Each butterfly at Site 4 was released in the
same subplot where it was caught. Site 5 was not so subdivided and all
marked individuals were released in the center of this .25 hectare study
plot. Release was effected by holding the butterfly with forceps, low-
ering the insect onto a wet leaf until it secured a purchase, and waiting
until the insect had uncoiled its proboscis and started drinking before
releasing the forceps. In this way, the initiation of escape behavior
upon release was avoided.
The capture-mark-recapture experiments performed on the ithomiine
aggregations at Eupatorium flowers at Sites 1 and 3 involved the same
data collection and marking techniques as the forest samples, but the
methods of collection and release were different. Beginning shortly af-
ter sunrise, all ithomiines and their mimics visiting the flowers were
collected at fifteen minute intervals throughout the morning until no
more butterflies remained. Between collecting periods, marking and re-
cording were done, and marked butterflies were held in small screen cages.
At the completion of the sample, the cage was moved to a central location
and the butterflies were allowed to fly away.
Preliminary studies on the reproductive morphology of ithomiines
were made during this study, but require further field work for their
completion. Female ithomiines of various estimated ages were dissected
under the microscope to count the number of eggs and ovarioles present
in the reproductive tract. The spermatophores present in the bursa copu-
latrix were counted to establish the minimum number of times each female
had mated. Drawings were made of fully inflated spermatophores. The
expanded androconial brushes of adult males were examined under the
microscope, drawn and measured, and the density of the androconial scales
ADULT ECOLOGY OF THE ITHOMIINAE
All of the ithomiine species at Limoncocha may be classified as
sylvestral although some species commonly fly along forest borders and
a few (e.g., Mechanitis isthmia) regularly enter clearings. Those
individuals that leave the forest interior, however, apparently do so
only for specific purposes, e.g., flower feeding (males) or oviposition
(females). On numerous sunny days I have watched as an ithomiine
strayed into a sun-lit trail or to the edge of a clearing, at which
point the butterfly immediately turned back into the deep shade of the
understory, usually dropping to a lower vertical level of flight. This
behavior has also been noted by other workers (e.g., Young, 1974a),
especially for the more scotophilic species, although on cloudy days it
may be much less pronounced.
The proximate cause of this behavior is probably the sudden increase
in light intensity above a critical level. Although the ultimate causes
of this negative phototropism are unknown, there are at least two likely
possibilities. One of the prime requirements for good ithomiine habitat
is high humidity. Several observers (e.g., Ross, 1967), including myself,
have noted that, given an area with a range of dampness, ithomiines are
much more likely to be found in the wetter areas, especially along
shaded streams. Those individuals that tolerate higher light intensi-
ties are more likely to meet with lower humidities and thus their
chances for survival may be diminished by the threat of desiccation.
The ithomiine requirement for forests with relatively high humidities
has consequences on a macrohabitat scale as well. In Mato Grosso,
Brazil, Collenette and Talbot (1928) described a vegetational "oasis"
of large trees shading a relatively open, moist understory in a region
otherwise composed of dry scrub forest or bamboo thickets. Within this
small area of luxuriant, riparian forest, Collenette discovered large
numbers of mimetic butterflies, mostly ithomiines, that were isolated
from other such concentrations by several kilometers of surrounding
This clumped distribution into "ithomiine pockets," as Brown has
termed them (Brown and d'Almeida, 1970), has since been confirmed for
ithomiine populations in the median-littoral forests of southeastern
Brazil (Brown and d'Almeida, 1970) and suggested for other localities
in the Neotropics (Brown, 1972). Ithomiine pockets have also been
observed in superficially homogeneous moist forests (Ross, 1967; Brown
and Benson, 1974) but here they are likely to be quite unstable and
their often close proximity (less than 500 m apart) results in considerable
overlap and fusion. Ithomiine pockets in seasonal forests are quite
localized during the dry season (but spatially unpredictable from year
to year) and high densities of ithomiines may occur (Brown, 1972). Dur-
ing the wet season these pockets become diluted as the butterflies track
the expansion of available habitat (Brown, 1972). This expansion and
contraction sequence is probably similar (on an ecological rather than a
geological scale) to the expansion and contraction of the neotropical
refugia during alternating wet and dry periods of the Quaternary. The
temporal and spatial dynamics of these ithomiine pockets have implica-
tions for mimicry theory to be discussed in Chapter 7.
A second possible reason for negative phototropism in ithomiines
is predator-mediated selection. Many of the clear-wing ithomiine species
apparently depend on the dappled lighting and shifting sunspecks against
the dark forest floor to conceal or break up their image while flying
in the forest understory. Many collectors have referred to the difficulty
of following the disembodied spots that represent a clear-wing ithomiine
weaving through the forest understory (e.g., Collenette and Talbot,
1928). Such protection is immediately forfeited, however, upon entering
the comparative brilliance of an open clearing on a sunny day.
Within the forest, ithomiine species seem to show a preference for
a particular light level, as suggested by their fidelity to a given
flight level in the understory. In general, the clear-wing species
are all found within two meters of the forest floor, while the tiger-
patterned ithomiines spend most of their time above the two-meter mark.
Ross (1967) found a similar division among the twenty Ithomiinae present
in his Sierra de Tuxtla (Mexico) study area. At Limoncocha, however,
each species within these two pattern complexes also has a characteristic
individual flight stratum, which may be broad or narrow depending on the
species. For example, Scada batesi characteristically flies at heights
of less than 50 cm, while Godyris zavaleta is most likely to be found
at heights between 1.0 and 2.0 m; all four Melinaea species are rarely
found below 5.0 m but may occupy much of the upper canopy region. It
has long been recognized that the light intensity of a tropical forest
decreases from the canopy to the floor (Allee, 1926) producing vertical
stratification in terms of light (and probably also in terms of humidity).
Recent work (Papageorgis, 1974) suggests that this vertical stratifica-
tion of light intensity is of primary importance in determining the
flight levels of different mimetic complexes of butterflies in tropical
forests, an hypothesis to be considered in Chapter 7. Further evidence
for ithomiine response to light intensity comes from my observations
that the perch and flight levels of ithomiines vary depending on the
amount of light penetrating a given layer of forest, although this
could also be interpreted as a response to changing humidity since rela-
tive humidity appears to be tightly correlated with light intensity in
the understory. In general, perch heights (and to a lesser extent,
flight levels) tend to be lower during periods of high light intensities
in the understory. Benson (1967) reported that Mechanitis isthmia
(=lycidice) in Costa Rica perch higher in the early morning (ca. 1 m)
than they do at midday or during the afternoon (ca. 15 cm), a phenomenon
that corresponds with the observations above, although the perch heights
are extremely low for Mechanitis. Since Benson's observations were made
during the dry season, the relatively low perch heights may indicate a
negative response by Mechanitis isthmia to a seasonal decrease in humidity
at higher levels in the understory.
The flight of ithomiines is normally slow and graceful, but may
become surprisingly rapid and determined if they are violently disturbed.
This "escape behavior" usually manifests itself in two ways. Tthomiines
that frequent the lower levels (below 3 m) of the forest tend to fly
downward and into thick vegetation when disturbed. Those species charac-
teristic of higher levels usually fly away at the same level of the dis-
turbance or arc upward toward the canopy. Such behavior suggests that
the escape reaction may be oriented by either positive or negative photo-
tropism. Flights of males during courtship and of females during oviposi-
tion are unique and will be described in Chapter 4.
The daily activity pattern for ithomiines appears to be roughly
the same for all species observed at Limoncocha. Ithomiines become
active at first light and may be seen flying and feeding as early as
0605 h at Limoncocha. The first activity of the day is feeding. Males
seek out flowers in open understory, in or along the edges of clearings,
or, for those species characteristic of higher flight levels, in the
forest canopy. Females are rarely attracted to nectar sources, or at
least not to those frequented by males. Instead, they are most often
seen feeding on bird droppings and other detritus of the forest interior.
Feeding for both sexes may continue intermittently throughout the day
in the forest understory, but visits to flowers in clearings by males
occur mainly in the early morning and late afternoon (see below).
Courtship and mating begin in mid-morning and usually continue through
mid-afternoon. Oviposition occurs predominantly in the afternoon, during
which time males may again seek out nectar sources. Unlike most diurnal
Lepidoptera (except for the crepuscular Brassolinae), ithomiines
are generally active until dusk. Some Mechanitis isthmia have been seen
flying in clearings as late as 1815 h, and ovipositing as late as 1835 h
(with only faint light on the western horizon) at Limoncocha.
In a very brief study during the dry season in Guanacaste Province,
Costa Rica, Benson (1967) found "that individuals of Mechanitis isthmia
spend on the average only .68 to 3.36% of their time in flight, with
the remainder of the time spent perched on leaves (although looked for,
no other behaviors were observed). This would be a very low figure
(averaging about 21 minutes per 12 h day) for any ithomiine in a wet
forest area, especially for a Mechanitis.' Although no time budgets of
behavior were constructed for any species at Limoncocha, a minimum
estimate of the time spent flying by Mechanitis isthmia (and all other
Mechanitis) would be two to three times that given by Benson. It is
quite possible that Benson's dry-season observations of a very low level
of flight activity in the Guanacaste seasonally deciduous forest reflect
adaptive behavior in response to the tropical dry season there, when
active butterflies would be faced with constant desiccating winds and
low humidity levels (T. C. Emmel, pers. comm.). Comparable observations
have not been made during the Guanacaste wet season.
All ithomiine species at Limoncocha rest (i.e., perch without
directed activity) during the day by perching on the upper surfaces of
leaves with their wings together over their backs. This is apparently
true for ithomiines in general, although Hymenitis (=Greta) diaphane on
Jamaica characteristically perches on the underside of leaves (Brown and
Heineman, 1972; Brown, 1973). The exceptional perching behavior of H.
diaphane may be unique, since Young (1972), after a detailed study
of the natural history of Hymenitis nero in Costa Rica, reported no
unusual perching behavior in this congeneric species.
Almost nothing is known about the resting behavior of ithomiines
at night. There are a few hints in the literature that roosting
aggregations may sometimes form, but these reports are poorly documented.
P. L. Guppy (recorded in Poulton, 1931) observed a roost of the black and
red Heliconius erato (=hydarus) in Trinidad (several species of Heliconius
are known to form gregarious roosts at night; see Turner, 1975) and
found that individuals of the tiger ithomiine.Tithorea harmonia megara
(=megara flavescens) were "not infrequently" perched in close proximity
to the Heliconius in the roost. The roost in question was hanging from
dried twigs about two meters above St. Ann's River under the shelter of
a bamboo thicket. The report implies, but does not state outright, that
individuals of both H. erato and T. harmonia, which have quite dif-
ferent patterns of aposematic coloration, returned to the roost on
consecutive nights. Faithfulness to a communal roost is now well docu-
mented for several species of heliconiines, including H. erato (Turner,
1971; Benson, 1972), but has not been reconfirmed for Tithorea. Turner
(1975), however, has recorded the unpublished observation by Vasconcelas
Neto and Keith Brown that Tithorea harmonia occurs in roosts of Heliconius
erato in Brazil, but the regularity of this association is not known.
Guppy also suggested that species in the genus Mechanitis might roost
gregariously. And indeed, A. M. Moss (recorded in Poulton, 1933)
observed "hundreds" of Mechanitis lvsimnia (=nesaea) in Bahia, Brazil,