Systematic survey of Coryphoid palms using foliar epicuticular wax and anatomical characters


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Systematic survey of Coryphoid palms using foliar epicuticular wax and anatomical characters
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Taylor, Yolander Renea, 1968-
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Table of Contents
    Title Page
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    Chapter 1. Introduction
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    Chapter 2. Anatomical and morphological study
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    Chapter 3. Epicuticular wax study
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    Chapter 4. Cladistic analysis
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    Chapter 5. Discussion
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    Literature cited
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    Biographical sketch
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Full Text







Copyright 1999


Yolander Renea Taylor


I am grateful to several people for the completion of

this work. The research staff of the Fairchild Tropical

Garden provided access to the extensive palm collection of

this garden. The SEM work was in part supported by funds

provided by the Botany Department and was conducted in the

Electron Microscopy Core Laboratory, Interdisciplinary

Center for Biotechnology Research, University of Florida,

Gainesville, Florida. Norris Williams, Mark Whitten, Wesley

Higgins and the Molecular Systematics Laboratory were ever

so gracious in allowing me to use their computers and

programs. My committee members Walter S. Judd, Scott Zona,

William L. Stern, Henry A. Aldrich, and David A. Jones were

always readily available to me during my tenure here. I

thank each one of them for helping me and guiding my

research. My fellow graduate students have also been

supportive, especially Kim Gulledge, Nico Cellense, and Reed


Last, but not least I thank my family. They have been

my rock. Their support has guided me throughout all my

endeavors. This work is dedicated to them, especially my

brother, who provided photographic support, and my mother,

Callie Taylor.



ACKNOWLEDGEMENTS .......................................................................................................... iii

A B S T RA C T ................................................................................................................................. v


I INTRODUCTION ................................................................................................... 1

Geographical Distribution ................................................................. 4
Morphological Characteristics of Palms ........................... 8
Current Classifications .................................................................... 15
Foliar Anatomy ................................................................................................... 16
Foliar Epicuticular Waxes ................................................................. 21
Research Objectives ..................................................................... 25

II ANATOMICAL AND MORPHOLOGICAL STUDY ....................................... 27

Introduction .................................................................................................. 27
Methods .................................................................................................................. 27
Character List .................................................................................................. 35

III EPICUTICULAR WAX STUDY .................................................................... 65

Introduction ................................................................................................... 65
Methods .................................................................................................................. 67
Epicuticular Wax Characters ..................................................... 68

IV CLADISTIC ANALYSIS ....................................................................................... 84

Cladistic analysis based on anatomical and
Epicuticular Wax Data ........................................................... 84
Combined Cladistic Analysis Based on Morphological
Anatomical, and Micromorphological Data ......... 108
Combined Cladistic Analysis Based on Anatomical,
Micromorphological and Morphological Data ...... 120

V DISCUSSION ............................................................................................................ 148

LITERATURE CITED ...................................................................................................... 155

BIOGRAPHICAL SKETCH ................................................................................................ 161

Abstract of Dissertation Presented to the Graduate
School of the University of Florida in Partial
Fulfillment of the Requirements for the Degree of
Doctor of Philosophy



Yolander Renea Taylor

August 1999

Chairman: Walter S. Judd, Ph.D.
Major department: Botany

Foliar epicuticular wax structures/patterns can provide

useful taxonomic characters. Use of the Scanning Electron

Microscope to view the epicuticular wax layer of palm leaves

allowed qualitative wax features to be readily

characterized. These characters were used in a cladistic

study of palms (Arecaceae), with an emphasis on the

Coryphoideae. These characters were used in order to expand

the number of phenotypic characters available for analysis.

It was found that epicuticular wax characters such as

crusts/layers and rods do help support the monophyly of

certain groups within the palms, e.g., the Coryphoideae and

Borasseae. However, these characters are often quite


homoplasious, as are many other morphological characters,

and therefore, they should not be used alone in a cladistic

study. Instead, they should be combined with numerous other

phenotypic and/or molecular features (as was done here). In

the analyses performed as part of this investigation certain

aspects of the current classification of Arecaceae are not

supported. The monophyly of Ceroxyloideae, Arecoideae, and

Calamoideae was called into question. The Coryphoideae are

indicated as monophyletic, but the large tribe Corypheae is

definitely non-monophyletic because Coryphinae and

Borassaeae form a well supported clade. Analysis of

combined data sets (e.g., epicuticular wax, vegetative

anatomy, morphology, and DNA) are shown to provide increased

resolution of infrafamilial clades.


Palms epitomize the monocots with their leaves and

sheathing leaf bases, parallel foliar venation, and

trimerous flowers (Uhl & Dransfield, 1987). Their most

obvious features, the coriaceous, plicate leaves and

arborescent habit, characterize the group. Leaves of palms

may be palmate, costapalmate, or pinnate (Figure 1-1), and

borne at the apex of a woody trunk. Palm inflorescences are

typically variously branched spikes, often with expanded

bracts. The fruits are drupes. Monophyly of the group is

well supported by morphological and molecular features

(Chase et al., 1995; Uhl & Dransfield, 1987; Uhl et al.,

1995; Zona, 1997).

Palms are among the most variable plants in the world.

They have a long cultural, medicinal, and commercial history

(Balick, 1986; Henderson, 1990; Hill, 1952; Morton, 1977;

Sullivan, 1995).

The palm family is pantropical with subtropical

extensions. The extreme limits of distribution are 44 N

latitude in Europe and 44 S latitude on the Chatham

Islands, near New Zealand (Corner, 1966). They are mainly

found in humid tropical areas, although few species do

Figure 1-1. Three characteristic palm leaf types (Uhl &
Dransfield, 1987).


fillet (pinna)

I, D tiO

DI ~steaf

venture into temperate regions but rarely do they become

established in deserts. Present limits of the family mark

the line where frost damage to living tissue becomes serious

enough to impede growth in competition with other vegetation

(Corner, 1966).

Geographical Distribution

Palms once had a much wider distribution than they do

now (Corner, 1966). The fossil record indicates that palms

were found in what today are unlikely places, including the

Arctic and subarctic zones (Uhl & Dransfield, 1987). In

North America, palm fossils from the Cretaceous period have

been found in Colorado, Alaska, Vancouver Island, Oregon,

South Carolina and possibly New Mexico during the Cretaceous

period (Uhl and Dransfield, 1987). Fruits and seeds have

also been discovered in the London Clay bed and Greenland

(Uhl and Dransfield, 1987). The climate in these areas

during the Cretaceous and early Tertiary was apparently much

more tropical than it is today and thus more conducive to

palm growth.

The earliest recorded palm fossils are the Coryphoid

palms Sabal magothiensis (Berry, 1911) and Palmoxylon

cliffwoodensis (Berry, 1916), which occurred in the

Santonian period of the Upper Cretaceous (Uhl & Dransfield,

1987). The earliest fossil pollen records of palms are of

Nypa and date from the Maestrichtian period (Dahglian,

1981). Palms are probably the most abundant monocots found

in the fossil record (Dahglian, 1981; Herendeen and Crane,

1995), possibly because of their tough leaves and woody

stems. Palms became more numerous and abundant during the

Eocene period, a time of widespread tropical forests, but

were more limited during the Oligocene as climatic changes

occurred. The fossilized palm fruits found in Eocene and

Oligocene deposits resemble the genera Sabal, Serenoa,

Livistona, Trachycarpus, and Nypa. During cooling in the

Miocene and Pliocene there was a gradual retreat of palms to

their present locations in tropical and subtropical

latitudes (Axelrod, 1950).

The present day disjunct distribution of palms was

probably greatly influenced by the break-up of Laurasia and

Gondwanaland and the subsequent colliding of land fragments.

Many palms are endemic and show very restricted or disjunct

distributions. Most palms, with the exception of Nypa and

Cocos do not have fruits suited for long distance dispersal

without animal intervention, yet many genera have wide gaps

in their geographical ranges (Zona and Henderson, 1989).

Evidence suggests that these restricted distributions,

disjunctions, and large gaps in ranges of genera are

probably the result of climatic changes (mainly involving

temperature fluctuations and hydrological conditions) and

the movement of land masses (Uhl & Dransfield, 1987).

Six subfamilies are usually recognized, distributed as

outlined below.

Coryphoideae consist of three tribes: Corypheae are

pantropical and subtropical; Phoeniceae are Old World

tropical and subtropical; and Borasseae are found on

landmasses adjoining the Indian Ocean (Uhl & Dransfield,

1987). Corypheae and Phoeniceae traditionally are

considered to be the least specialized members of the

subfamily and are thought to be Laurasian in origin. The

Borasseae, are more specialized and believed to have a

Gondwanaland origin (Uhl & Dransfield, 1987).

Three tribes comprise the Calamoideae: Calameae are

presently found in Asia, Central and South America, and

Africa; Lepidocaryeae occur mostly in northern South

America. Uhl & Dransfield (1987) proposed that early

radiation of Calamoid ancestors occurred in northern

Gondwanaland followed by dispersal to Southeast Asia along

the shores of the Tethys Sea. Then representatives of the

group are thought to have dispersed to South America before

its separation from Africa; this dispersion was followed by

extinction of many taxa in Africa in relatively recent


Nypoideae occur today in Southeast Asia and the western

Pacific islands. Fruits of Nypa are well adapted for

dispersal by ocean currents. The fossil record indicates

that Nypa was once found in Europe, North and South America

and Australia. The genus probably has a Laurasian origin

because it was frequent along the Tethys shores (Uhl &

Dransfield, 1987).

Ceroxyloideae comprise three tribes: Cyclospatheae are

endemic to the Caribbean; Ceroxyleae and Hyophorbeae have

disjunct austral distributions. The breakup of Gondwanaland

may explain the current disjunct distribution of this

subfamily (Uhl & Dransfield, 1987).

Arecoideae are divided into six tribes and constitute

the largest subfamily of palms. The origin and dispersal

patterns of this group are uncertain. The center of

distribution for Caryoteae is in Southeast Asia and

Indochina. Iriarteae may have a South American origin

because only a few taxa occur outside of this continent.

Podococceae are restricted to the tropical rainforests of

Africa. It is believed that there were more kinds of palms

in Africa in the past, but many became extinct due to

Pleistocene climatic changes (i.e., repeated periods of

aridity) which have affected that continent. Areceae are

found in the Americas, West Africa, Madagascar, India and

Nicobar Islands, Papuasia, the Mascarene Islands, Seychelles

Islands, Sri Lanka, Malesia, and the Philippines. Cocoeae

are found in the Americas, equatorial and southern Africa,

the Pacific region, and Madagascar. Present day

distributions may suggest an origin in West Gondwanaland

with subsequent radiation in the Americas. Geonomeae occur

in Mexico, Central to South America, and the Caribbean.







apparatus. All except silica bodies and ultraviolet

absorbing compounds are probably synapomorphies.

Palms are trees, shrubs, or lianas, with erect or

prostrate, usually unbranched stems; their roots are

mycorrhizal (Zomlefer, 1994). Leaves of palms are large,

simple to palmately or pinnately compound, plicately folded,

and often have a hastula (Fig. 1-1). Generally palm leaf

segments will have either induplicate or reduplicate

plications. The leaves may be palmate, costapalmate or

pinnate (Fig. 1-1). Induplicate palms are restricted to the

Coryphoideae and the tribe Caryoteae (of Arecoideae). All

other palm groups have reduplicate plications (Uhl &

Dransfield, 1987).

Inflorescences of palms are determinate and often

paniculate to compound-spicate. Prophylls are always

present and may be numerous to few and small to very large.

Inflorescence bracts may also vary in number and are

sometimes enlarged and woody (Zomlefer, 1994).

Palm flowers are actinomorphic, perfect or imperfect,

hypogenous, usually sessile, and usually small. The calyx

is ordinarily composed of three distinct to connate,

imbricate, and often persistent sepals. The corolla

comprises three petals, which are distinct to connate,

leathery or fleshy, and usually inconspicuous. The

androecium contains six, biseriate stamens, but sometimes

they are numerous (due to a secondary increase). Filaments

are distinct to variously connate and/or adnate to the

petals; anthers are basifixed or dorsifixed, and dehisce by

longitudinal slits.

The gynoecium is generally apocarpous (may also be

psuedomonomerous), one to three carpellate, or syncarpous to

three carpellate; the ovary is usually superior, with basal,

axile, or apical placentation. One to three styles may be

present and the stigmas are erect or recurved. Fruits are

drupes or nutlike structures, with a fleshy, fibrous, or

leathery mesocarp; there are usually one to three (i.e., one

per carpel) and the endosperm is copious, homogeneous or

ruminate, and oily or occasionally hard; the embryo is

minute (Moore, 1976; Uhl & Dransfield, 1987; Zomlefer, 1994;

Zona, 1997).

Stems of palms contain peripheral apical meristems,

which are largely responsible for growth in width

(Tomlinson, 1990). The tissues have tannins, raphides and

silica (Tomlinson, 1990). Epicuticular waxes are present

and generally are of the Strelitzia-type as described later

(Barthlott and Frolich, 1983).

Characteristics of the subfamilies of palms as noted by

Uhl et al.(1987) are summarized below:

Coryphoideae are hermaphroditic, dioecious,

polygamodioecious, or polygamonoecious, but never strictly

monoecious. Their leaves are usually palmate or

costapalmate, rarely undivided or pinnate, and plication is

almost always strictly induplicate. Interfold splits occur

in three genera, and the plication is reduplicate in

Guihaia. Flowers are solitary or in cincinni, but are never

borne in triads (i.e., a cluster with a central pistillate

flower and two lateral staminate flowers). The flowers have

three sepals, three similar petals, six stamens in two

whorls of three, and three, free to variously connate


Members of the Phoeniceae have pinnate leaves and basal

leaflets modified as spines. Leaves of Corypheae are

palmate or costapalmate. The plants are usually

hermaphroditic, or polygamodioecious, rarely strictly

dioecious. If the plants are dioecious, the flowers are not

dimorphic. Rachillae lack deep pits and the endocarps are

usually thin, crustaceous or cartilaginous. Leaves of

Borasseae are palmate or costapalmate. Plants are dioecious

with strongly dimorphic flowers, and the staminate and

sometimes the pistillate flowers are borne in deep pits

formed by connation and adnation of rachilla bracts. The

endocarp is very thick and hard (Uhl & Dransfield, 1987).

Members of Calamoideae are easily distinguished by

their distinctive fruits, which contain overlapping scales

usually arranged in neat rows (Uhl & Dransfield, 1987).

Plants are hermaphroditic, monoecious, dioecious, or

polygamous. They are often fiercely armed. Leaves are

pinnate, or less commonly palmate and reduplicate. The

inflorescence is often highly branched, and parts are

frequently adnate. Bracts are usually tubular with flowers

that are almost always borne in dyads or dyad derivatives.

Unisexual flowers are only slightly dimorphic. The ovary

and fruit, as mentioned above, are covered with overlapping,

recurved scales (modified hairs). The ovary is incompletely

trilocular with basal anatropous ovules and micropyles

facing the center of the gynoecium. The pericarp is usually

thin at maturity, with an undifferentiated endocarp. One to

three seeds are usually produced, and each has a thick

sarcotesta. Calameae have pinnate leaves; Lepidocaryeae

have palmate or shortly costapalmate leaves Uuhl and

Dransfield, 1987).

Nypoideae are monoecious. Stems are prostrate with

dichotomous branching, leaves are pinnate and plication is

reduplicate. A pistillate head with lateral branches ending

in short spikes of staminate flowers terminates the

inflorescence. Flowers are extremely dimorphic. Six linear

distinct perianth parts are present and similar in plants of

both sexes. Three stamens are present, united in a column.

Three, free irregularly polyhedric carpels are curved and

angled with a funnel-shaped stylar opening. The fruiting

head is large, globose, and composed of irregularly

compressed and enlarged carpels with or without seeds. This

subfamily contains only the species Nypa fruticans, a

mangrove palm (Uhl & Dransfield, 1987).

Ceroxyloideae contain tall, moderate, or small,

solitary or clustered unarmed plants. They are

hermaphroditic, monoecious, or dioecious. The leaves are

regularly or irregularly pinnate and reduplicate.

Crownshafts may or may not be present. The inflorescence

contains three prophylls and usually several peduncular

bracts. When flowers are unisexual, they are only slightly

dimorphic. The gynoecium is syncarpous and triovulate.

Bisexual flowers borne on stalks characterize the

Cyclospatheae. Ceroxyleae are dioecious with unisexual

flowers borne singly on short stalks. Flowers of

Hyophorbeae are unisexual and sessile (Uhl and Dransfield,


Arecoideae are monoecious. Leaves are pinnate and

plication is reduplicate (or rarely induplicate in

Caryoteae). The flowers are borne in triads with a central

pistillate flower with two staminate ones. The group

contains six tribes: Caryoteae, Iriarteeae, Geonomeae,

Areceae, and Cocoeae (Uhl & Dransfield, 1987). Caryoteae

frequently show basipetal production of flowers. Leaves are

pinnate or doubly pinnate, and plication is induplicate.

The inflorescences are sometimes bisexual or unisexual due

to reduction of the triads. In the Iriarteeae the leaves

are also pinnate and plication is reduplicate. The flowers

are sessile. In the Podococceae the inflorescences are

spicate with flowers in sunken pits. The leaves of members

of this group are pinnate and plication reduplicate. The

Geonomeae also have pinnate leaves, reduplicate plication

and flowers sunken in pits (on rachillae). The petals of

staminate and pistillate flowers are basally connate and

form a soft tube. In Areceae the gynoecium is usually

pseudomonomerous (but very rarely triovulate). When

triovulate, the fruit is usually only 1-seeded. Leaves are

pinnate and reduplicate; a crownshaft is sometimes present.

In Cocoeae, as in other arecoid palms, leaves are pinnate

and plication is reduplicate, and flowers have a trilocular

and triovulate gynoecium. The fruit has a thick and bony

endocarp, usually provided with three pores; the

inflorescence is associated with a large persistent and bony

bract (Uhl & Dransfield, 1987).

Phytelephantoideae are moderate to rather large and

acaulescent or erect unarmed dioecious palms. Leaves are

pinnate and plication is reduplicate and inflorescences are

markedly dimorphic. The prophyll is rather short and

usually obscured by the leaf sheath, with one peduncular

bract. The staminate inflorescence is headlike, with

multiparted flowers, and a reduced perianth but numerous

stamens. Pistillate flowers are solitary and crowned with a

perianth of elongate fleshy sepals. The fruits are 5-10-

seeded and borne in a congested headlike cluster. The

mesocarp cracks to form irregular, fibrous, pyramidal warts.

The seed, with its hard endosperm, is enclosed in a hard,

thin, smooth, pyrene (Uhl & Dransfield, 1987).

Current Classification

Arecaceae are diagnosed by the series of shared

characters, as mentioned previously. Traditionally, palms

were thought to be related to Pandanaceae, Cyclanthaceae,

and Araceae. Bentham & Hooker (1883) placed them between

Juncaceae and Cyclanthaceae. Pandanaceae and Cyclanthaceae

are also woody and share with palms the arborescent habit,

large and sometimes plicate leaves, and rather small, drab

flowers. Of course, Araceae are herbs or vines. It has

since been shown that palms are only superficially similar

to Araceae, Cyclanthaceae, and Pandanaceae (Chase et al.,

1993; Duvall et. al, 1993). They differ because palms do

not have compound vascular bundles while, Pandanaceae and

Cyclanthaceae do. Arecaeae have Strelitzia-type waxes while

the Pandanaceae, Cyclanthaceae, and Araceae have various

other wax types. Recent DNA data (i.e. rbcL nucleotide

sequences) reinforce these two phenotypic characters,

placing Arecaeae as sister to Commelinanae (Chase et al.,

1995). The position of Arecaeae as sister to Commelinanae

may be problematic. Stevenson & Loconte (1995) placed palms

between Juncales and Poales (see Fig. 1-2), while Chase et

al. (1995) put the group as sister to all other Commelinoid

taxa (see Fig. 1-3). The latter placement is supported by

the lack of starch in the endosperm of palm seeds.

Although Arecaceae are clearly monophyletic, more work

is necessary to determine infrafamilial phylogenetic

relationships, and some currently recognized tribes and

subtribes may not be monophyletic. From a cladistic

analysis of morphological and chloroplast DNA restriction

site characters, Uhl et al. (1995) hypothesized that two of

the six subfamilies of Palmae do not constitute clades:

Ceroxyloideae and Arecoideae are polyphyletic and

paraphyletic, respectively (Uhl et al., 1995). The same

analysis supports the monophyly of the tribes of

Ceroxyloideae. The tribes of Arecoideae, however, are not

all monophyletic. Areceae is clearly paraphyletic (Uhl et

al., 1995). Nypoideae with only one species, was used to

root the tree.

Foliar Anatomy

Anatomical studies have been used in plant phylogenetic

studies because they are often taxonomically conservative,

Figure 1-2. Cladogram showing Monocot relationships; based
zn morphological characters. Note placement of Arecaceae.
Stevenson & Loconte, 1995)


Hypoxidaceae ^Velloziales
- Bromeliaceae .Bromeliflorae.
-- Haemodoraceae
i-- Philydraceae
-- Pontederiaceae
--- Aponogetonaceae
S -" Butomaceae
iUmnochantaceae Alismatales
-.. __ I-cAlismataceae
i -- Scheuchzeriaceae
r_ Juncaginaceae
----- ~Potamogetonaceae
<*- Alismatidae ,- Hydrocharitaceae
t- Posidoniaceae
Najadaceae Najiaies
-4- Convmmida Zosteraceae
..-- Zannichelliaceae
|-- Hydatellaceae
__ Sparganiaceae Typhes
_-- Commelinaceae
-I--- Rapateaceae
--- Eriocaulaceae Commehnales
-- Mayacaceae
-- Xynridaceae
--_ --- Cyperaceae
humiaceae juncaies
_- Juncaceae
Arecaceae +
Ecdeiocoleaceae Poales
Restionaceae ioe
'e- Cantrolemidaceae

Figure 1-3. Cladogram showing monocot relationships; based
on taxa common :o both morphological and molecular
analyses. Numbers above line equal branch support. Numbers
below equal bremmer support. Note placement of Arecaceae
(Chase et al. 1995).

- Musaccae
Hcliconia r
Zingiberaceae .
Arecaceae +
Zosteraccac ,
SZanniclielliaceae |
- Juncaginaceae
SApoiwgelon ;
Najas JQ
Acorus o
- Aristolochiales
Nymplieales 1(1
SPiperales 0

and because their use allows an increase in the number of

potentially phylogenetically informative features. In this

study I used foliar anatomical characters because the leaf

is the most obvious and striking organ of the palm, and such

characters had not previously been employed in phylogenetic

studies of this group. Foliar characters for the palms are

abundant and easy to access. Tomlinson (1961) studied the

palms intensively and suggested morphological and anatomical

characters that are shared by certain genera and tribes.

Morphological features and anatomical characters were used

for the current classification of the subfamilies and tribes

of the palms, but these were not assessed from a cladistic

standpoint (Uhl and Dransfield, 1987; Dransfield and Uhl,

1998). Uhl et al. (1995) used several morphological

characters in their phylogenetic analysis (along with DNA

characters), but they did not use many anatomical features.

Tomlinson (1961) considered many of the anatomical and

morphological characters used in his study to be

taxonomically valuable. My analysis will show the taxonomic

value of Tomlinson's assertions.

Foliar Epicuticular Waxes

Foliar epicuticular wax is the outermost layer of wax

present on the leaf surface. This wax accumulates in

response to light, continually over time, and therefore, the

older a leaf, the more wax it may contain (Martin & Juniper,

1970; Taylor, 1995). This continual production of wax is

in response to environmental factors such as wind and rain

that may remove some of the previously deposited wax (Martin

& Juniper, 1970). Wax is synthesized by epidermal cells and

exits to the surface as droplets through pores in the cell

wall (Taiz & Zeiger, 1998). Although the production of wax

is under genetic control, the environment plays a major role

in the thickness, configuration, and distribution of the

waxes (Baker, 1974; Martin & Juniper, 1970). Studies with

Arabidopsis do show correlations between epicuticular wax

structures and chemical composition (Rashotte et al.,

1998). Correlations have been found between chemical

composition and epicuticular wax structure (Baker, 1982;

Preece & Dickinson, 1971).

Certain plants and plant groups have definite foliar

epicuticular wax patterns (Benhke & Barthlott 1983; Hallam &

Chambers, 1970; Whitecross & Armstrong, 1972). Most of the

work showing taxonomic significance of these epicuticular

wax patterns and structures has been done on dicots, while

much of the work on monocots deals with epicuticular wax

structure and chemical composition (Barthlott and Theisen,

1995; Weiller et al, 1994; Denton, 1994; Machado and Barros,


The epicuticular wax layer protects the plant by

providing a barrier against water loss, various air-borne

chemicals, and invasion by pathogens (Juniper & Jeffree,

1983). Epicuticular waxes repel water thereby possibly

slowing germination of fungal spores because moisture is

necessary for the growth of most fungi (Taiz & Zeiger,

1998). It has been shown that the more dense the

epicuticular wax layer, the more water repellent the surface

(Neinhuis & Barthlott, 1997). Certain epicuticular waxes

may deter foraging activity of certain insects (Salatino et

al., 1998).

As noted by Barthlott et al. (1998), De Bary first

classified waxes into four categories layers or crusts,

granules, rodlets, and heaped coverings. Since that time

epicuticular waxes have been further categorized and used as

taxonomic tools. Benhke & Barthlott (1983) found that

certain families of Angiosperms have particular epicuticular

wax patterns; some of these are taxonomically significant.

After carefully studying over 13,000 plant specimens,

Barthlott & Frolich (1983) classified four major types of

waxes, the Convallaria-type, Streliztia-type, Berberis-type,

and Aristolochia-type. The Convallaria-type and the

Streliztia-type are restricted to the monocots. They do

not, however, occur in the same families (Barthlott and

Theisen, 1998). The Convallaria-type (parallel oriented

platelets) is characteristic of Liliales, Asparagales, and

Burmanniales. The Strelitzia-type (longitudinally

aggregated rodlets) is characteristic of Arecaceae,

Commelinanae (including Zingiberales, Bromeliales, and

Velloziales) (Barthlott and Frolich, 1983). The

Aristolochia-type of epicuticular wax (transversely ridged

rodlets) is characteristic of ancestral woody angiosperms,

and the Berberis-type (tubular crystals) is characteristic

of ranunculid families and gymnosperms (Hennig et al.,

1994). Barthlott et al. (1998) developed the most recent

and most detailed classification of epicuticular wax

structures and patterns. In his 1998 paper he expanded the

categories and suggested that these characters are

taxonomically significant. Much of his terminology is used

for the epicuticular wax characters in this cladistic study.

Of the four wax types, the Strelitzia-type is found in

palms. Chemical analysis of Strelitzia-type rodlets shows

they consist exclusively of aliphatic wax lipids, mainly

esters (Meusel et al., 1994). Other wax patterns are found

in palms as well as other chemical compositions (Garcia et

al.). Although it previously has been shown that

epicuticular wax structures and patterns are useful

taxonomically, they should, of course, not be used alone to

assess phylogenetic relationships. Meusel et al. (1994)

have shown that Benicasa hispida, a eudicot (Cucurbitaceae),

has rodlets very similar to those found in many monocots.

The chemical composition of the wax rodlets in Benicasa are

triterpenol acetates and triterpenols. This similarity

suggests that convergent evolution may be a problem in

higher-level analyses employing only epicuticular wax

structures and/or patterns, because the waxes of differing

chemical composition may have similar structures and/or

pattern. As with all phylogenetic analyses, to produce more

reliable cladistic hypotheses, wax characters should be used

along with other morphological and anatomical characters.

Research Objectives.

Since infrafamilial relationships are still rather

problematic in the Arecaceae (Uhl et al., 1995), this

project surveys the palms using foliar epicuticular waxes,

anatomical characters, and morphological features, with an

emphasis on genera within the Coryphoid clade (i.e.,

Coryphoideae). Variation in these characters is used in

cladistic analyses to assess phylogenetic relationships

within the family (and especially within Coryphoideae) as

well as character trends. Traditionally, morphological and

anatomical characters were used in phylogenetic analyses

because they were the only structures available for study.

We now have access to other features, such as epicuticular

waxes or molecular (i.e., DNA) data. It has been shown that

the most resolved cladograms are formed in analyses that

combine all available data (Soltis et al., 1998). These

relationships within the Coryphoid clade (and within palms)

will be re-assessed using my anatomical, micromorphological

and morphological characters, both alone, and in combination

with the features used by Uhl et al. (1995). Finally, the

pattern of variation of epicuticular wax characters on the

combined data trees should be instructive with respect to

the phylogeny of palms.



Tomlinrison (1961) conducted an extensive study of palm

anatomy and determined numerous potentially useful taxonomic

characters. Additional characters were highlighted in a

broader study on palms that included morphology and economic

usage (Tomlinson, 1990). However, in neither publication

were characters used in phylogenetic analyses. Some

characters suggested to be of taxonomic significance by

Tomlinson (1961, 1990) are listed in Table 2-1.


A complete list of species used in this study is

provided in Table 2-2. Anatomical samples and voucher

specimens were taken from cultivated plants at the Fairchild

Tropical Garden in Miami, Florida. Fifteen centimeter

segments were cut from the middle half of one side of a

mature leaf. Several 1cm squares were then cut out of the

segments and placed in a 70% alcohol solution. Anatomical

characters were investigated by free-hand sectioning with a

single-edged razor-blade of this preserved material. Thin

sections were stained with phloroglucinol and observed under

Table 2-1. Diagnostic characters and their respective genera
from Tomlinson (1961, 1990):
1. Isolateral Symmetry of the lamina: Bismarkia,

Copernicia Borrassus, Hyphaene, Latania, Medemia,

Nannorrhops, Phoenix, Sabal, Serenoa, Trithrinax.

2. Multicellular hairs with an elliptical base of usually

many sclerotic cells and a distal expanse of thin-

walled cells: Borassus, Hyphaene, Medemia, Pritchardia,

Rhapidophyllum, Lodoicea, Trachycarpus, Chamaerops.

3. Basal cylinder of sclerotic cells surrounding 1 or more

thin walled cells: Arenga, Caryota, Wallichia.

4. Epidermis with long and short cells: Licuala,


5. Adaxial epidermal cells with distinctly sinuous walls

in surface view: Lacosperma, Borassodendron.

6. Stomata surrounded by sclerotic, pitted epidermal

cells: Pelagodoxa.

7. Guard cells of stomata sunken: Borassus, Hyphaene,

Nannorrhops, Nypa.

8. Guard cells with transverse striations on the ledges:

Arenga, Caryota.

9. Guard cells with only one cuticular ledge:


Table 2-1 continued.
10. Guard cells with several cuticular ledges: Nypa.

11. Adaxial hypodermis with two or more layers, usually 1

abaxial hypodermis: Jubaea, Lodoicea.

12. Adaxial and abaxial hypodermis with two or more layers:

Hyphaene, Nypa, Nannorrhops, Borassus, Latania,

Medemia, Washingtonia.

13. Hypodermis wholly fibrous: Pseudophoenix.

14. Substomatal hypodermis cells lobed with subdividing

chamber: Borassodendron, Latania, Phoenix, Borassus.

15. Nonvascular fibers mostly in strands continuous with

and usually indistinguishable from fibrous buttresses

of veins: Borassus, Butia, Hyphaene, Jubaea, Latania,

Medemia, Licuala.

17. Veins in abaxial mesophyll mostly in contact with

abaxial surface layers: Ceroxylon.

18. Veins in adaxial mesophyll mostly in contact with

adaxial surface layers: Borassodendron, Corypha,


19. Veins almost all attached to one or both surfaces by

fibrous buttresses: Bismarckia, Borassus, Butia,

Hyphaene, Jubaea, Latania, Medemia, Nannorrhops, Sabal.

20. Midrib region not prominent, no vascular bundle:


Table 2-1 continued.
21. Midrib region prominent including many independent

vascular bundles and a single wide band of expansion

cells: Hyphaene, Latania, Lodoicea, Bismarckia,

Borassodendron, Medemia, Borassus, Corypha, Livistona,

Washingtonia, Trachycarpus, Licuala, Acoelorraphe,

Zombia, Brahea, Pholidocarpus, Serenoa, Rhapis, Sabal,

Cryosophila, Johannesteijsmannia, Pritchardia,

Rhapidophyllum, Copernicia, Trithrinax, Coccothrinax,

Chamaerops, Nannorrhops, Thrinax.

Table 2-2. Genera and Species of palms surveyed (arranged
according to the classification of Uhl & Dransfield, 1995).
FTG Ascession number (or collector and collector's number)
follow each species. All specimens vouchered at Fairchild
Tropical Garden unless otherwise noted.
Coryphoi deae



Coccothrinax miraguama (Kunth)Becc., 5861F

Rhapis excelsa Henry ex Rehder, 943043

Chamnaerops humilis Linn., RM157A

Thrinax morissii H. Wendl., 4725

Rhapidophyllum hystrix H. Wendl. & Drude,



Copernicia prunifera (Mill.) H. E. Moore


Acoelorraphe wrightii H. Wendl. ex Becc.,


Livistona chinensis R. Br., 4254

Serenoa repens (Bartram) Small, (Taylor 1

USF herbarium)

Licuala grandis H. Wendl., 79536A


Nannorrhops ritchiana H. Wendl., 60756A

Kerriodoxa elegans J. Dransf., 84213B

Table 2-2 continued.

Sabal palmetto (Walter) Lodd. ex Schult. &

Schult. f., (Taylor 26 UF herbarium)


Phoenix acaulis Buch-Ham. ex Roxb, 86524A



Latania loddigesii Mart., 72519

Lodoicea maldivica Pers. ex Wendl., 961379B

Hyph a eni nae

Hyphaene petersiana Klolzsch ex Mart., 57129

Calamol deae



Calamus concinnus Mart., 71375



Pseudophoenix sargentii H. Wendl., 58872


Ravenea hildebrandti H. Wendl. ex Bouche,


Table 2-2 continued.


Arenga microcarpa Becc., 60741A



Socratea exorrhiza H. Wendl., 93133C



Dypsis cabadae (H. E. Moore) Beentje & J.

Dransf., 2282B


Chambeyronia macrocarpa Vieill., 77147


Drymophloeus oliviformis Scheff., 5453A


Pinanga curranii Becc., 92161K


Dictyosperma album H. Wendl. & Drude, 88373A



Allagoptera arenaria Kunth, 714420


Bactris gasipaes Kunth, 66342A


Table 2-2 continued.

Calyptronoma occidentalis (Sw.) H.E. Moore,



Nypa fruticans Wurmb, (On grounds of

Montgomery Botanical Center)

a compound microscope. Drawings of thin-sections were made

using a Bausch and Lomb projector scope.

A portion of each segment was cleared to show venation

patterns. The procedure for leaf clearings was modified

from Zona's (1990) study of the genus Sabal. Tissue

segments were soaked in 2.5% NAOH solution for 24 hours.

These samples were then washed in a 33% commercial bleach

solution for ten minutes. The samples were then washed with

water for ten minutes to remove the bleach, and stained with

a 50% safranin solution.

Morphological characters were observed in the field (at

Fairchild Tropical Garden) or in herbarium specimens (at FTG

or FLAS), supplemented from information taken from the

literature (especially Uhl et al., 1995).

Character List

The anatomical and morphological characters used for

this study are characters 1-28 and 38-43 listed in Table 2-

3. These characters are based on those of Tomlinson (1961,

1990) but are modified based on my own observations of the

pattern of variation observed in studied taxa. Characters

showing extensive infrataxon variation were not used. In

addition, certain characters were excluded because they were

invariant, or characterized only a single taxon. Some

features showed continuous variation, e.g., lignified xylem

Table 2-3. Potentially phylogenetically informative
anatomical, vegetative morphological, and
micromorphological characters observed in this study.
Ancestral state (0), derived state (1); based on Nypa
as an outgroup.
1. Plication is reduplicate (0); induplicate (1).

2. Leaves pinnate (0); palmate (1); costapalmate (2).

3. Dichotomous branching present (0); absent (1).

4. Petiole split at base (0); not split (1).

5. Hastula absent (0); present (1).

6. Hypodermis present (0); absent (1).

7. No fibers forming hypodermal layer/s (0); fibers

forming hypodermal layer. (If no hypodermis is present

code as "?" )

8. Hypodermis other than one layer adaxially and

Abaxially (1); hypodermis of one adaxial layer and one

abaxial layer. (Code "?" if missing.)

9. Hypodermis of 2 or more layers adaxially (0);

hypodermis of only 1 layer adaxially(1). (Code "?" if


10. Hypodermis of 2 or more layers abaxially (0);

hypodermis of only 1 layer abaxially (1). (Code "?" if


11. Hairs present (0); hairs absent(l).

12. Dorsoventral lamina (0); isolateral lamina (1).

13. Distinct palisade mesophyll present (0); distinct

palisade absent (1).

Table 2-3 continued.
14. Adaxial and abaxial palisade layer present (0);

adaxial and abaxial palisade absent or only adaxial

layer present (1).

15. Nonvascular fibers not protruding (0); Fibers

protruding (0).

16. Nonvascular Fiber bundles (of three or more cells) in

Mesophyll (0); No fiber bundles in mesophyll(1).

17. Solitary nonvascular fibers absent (0);

Solitary nonvascular fibers present (1).

18. Nonvascular fiber bundles lacking on leaf surfaces(0);

attached to abaxial hypodermis or epidermis (1);

attached to adaxial hypodermis or epidermis (2);

bundles attached to both surfaces (3).

19. Nonvascular fiber bundles more prominent near abaxial

surface than near adaxial surface (0); bundles more

prominent near adaxial surface than near abaxial

surface (1); bundles the same on both surfaces (2).

(Code as "?" if not present.)

20. Large and small fiber bundles on the same surface (0);

Uniform fiber bundles on the same

Surface (1). (Code as "?" if not present.)

21. Veins not protruding (0); Veins protruding (1).

22. Large veins attached to both surfaces (0); all veins

independent of surface layer (1); small veins

independent of surface layers and/or small veins

Table 2-3 continued.
independent of surface layers and large

veins attached to abaxial surface (2); small veins

independent of surface layers and large veins attached

to adaxial surface (3); small veins attached to abaxial

surface only and large veins attached to both surfaces

(4); small veins attached to adaxial surface only and

large veins attached to both surfaces (5); all veins

attached to one or both surfaces by well developed

bundles sheath extensions (6); all veins attached to

adaxial surface (7).

23. Large and small vascular bundles outside midrib

present (0); uniform vascular bundles outside midrib

absent (1).

24. Expansion tissue on either side of midvein (0); above

midvein (1).

25. Expansion tissue conspicuous (three or more large

expansion cells prominent) (0); inconspicuous(l).

26. Vascular bundle in midrib present (0); absent (1).

27. Midrib not prominent with two or more independent

vascular bundles (0); midrib prominent with two or

more independent vascular bundles (1).

28. Midrib prominent with vascular bundles enclosed in a

common layer of fibers (0); each vascular bundle

enclosed by its own sheath of fibers (1).

Table 2-3 continued.
29. Coalesced epicuticular wax rods not present (0);

present (1).

30. Curled coalesced epicuticular rods absent (0); present

(1). (code "?" if no rods present).

31. Smooth epicuticular wax absent (0); present (1).

32. Epicuticular wax crystalloids covering entire surface

(0); epicuticular wax crystalloids lacking (1);

Epicuticular wax crystalloids scattered (2).

33. Crust layers of epicuticular wax absent (0);

Crust/layers of epicuticular wax present (1).

34. Platelets absent (0); Platelets present (1).

35. Fissured layers absent (0); present (1).

36. Granules present (0); absent (1).

37. Membranous platelets absent (0); present (1).

38. Branching transverse veins absent (0); such veins


39. Transverse veins present small (0); transverse veins

present large (1).

40. Looping transverse veins present (0); absent(l).

41. Long transverse veins (i.e. veins that cross 3 major

longitudinal veins) absent (0); long transverse veins

present (1).

42. "v" or "A" shaped lamina(0); "T" shaped lamina (1).

43. Adaxial stomata on segment absent (0); adaxial stomata

on segment absent (1).

walls, lignified vascular and nonvascular fiber bundles, and

were thus difficult to delimit into discrete states; these

characters were also excluded from analysis.

The polarity of the morphological/anatomical character

states used in the study were determined by reference to

Nypa, which is supported as an appropriate outgroup based on

the higher-level phylogenetic analyses of Uhl et al. (1995).

All multistate characters were considered unordered.

Particular characters are discussed in more detail below.

Morphological characters. Vegetative morphological

characters include induplicate or reduplicate plications;

palmate, costapalmate, or pinnate leaves; dichotomous

branching of the stem; condition of the petiole base; and

the presence or absence of a hastula.

Hypodermis. Characters 6-10 involve the presence, type,

position, and number of hypodermal layers. Figure 2-1 is an

example of a fibrous hypodermal layer as represented in

Pseudophoenix sargentii.

Epidermal hairs and stomata. The presence or absence of

hairs on the epidermis, and stomata on the adaxial surface

of the epidermis are used as characters.

Palisade mesophyll. Characters 13 and 14 deal with the

presence and placement of the palisade mesophyll. An

example of a distinct palisade layer is given in Figure 2-1.

Figure 2-1. Cross-section of Pseudophoenix sargentii. (A)
Cross section of midvein showing common sclerotic fibers
(sf) enclosing one vascular bundle (vb) and expansion
tissue (et) on either side of midvein. (B) Enlargement of
leaf segment cross-section showing fibers (f), fibrous
hypodermal layer (fh), palisade mesophyll (pm), vascular
bundles (vb) and protruding fibers (pf).


f h



Figure 2-2. Diagram of cross-section of leaf segment of
Kerriodoxa elegans. Note vascular bundles surrounded by
fibers, solitary fibers (fc) in mesophyll, one-layered
hypodermis (h).

-- """-" h

"^~o 0,Ab


100 urn


^)~ f e/_"----gP

Fibers. Characters 15-20 involve the presence of fibers in

bundles (three or more fiber cells in a bundle) and the

position of the fiber bundles. Figure 2-1 shows nonvascular

fiber bundles protruding from the abaxial surface. Figure

2-2 shows solitary fibers (three or fewer fibers cells in

the mesophyll).

Veins. Characters 21-23 are derived from the position of

veins in the mesophyll. Some veins are pectinate, see

Figure 2-3. Veins may be attached to the adaxial and/or

abaxial surface, some laminas have large and small vascular

bundles, and some others have fibrous buttresses, i.e.,

fibrous extensions attached to the vascular bundle (see Fig.


Expansion tissue. The expansion tissue is located in the

midrib region. It is believed to play a role in leaf

folding. Characters 24 and 25 deal with the position of

expansion tissue in the midrib (see Fig. 2-5).

Vascular bundles in midrib. Characters 27 and 28 deal with

differences in the midrib (see Figs. 2-6 and 2-7). The

midrib of Livistona is characterized as one with independent

vascular bundles, because the fibrous layer does not

surround all bundles.

Pattern of transverse veins. Variation in the pattern of

commissural veins with respect to longitudinal veins

Figure 2-3. Diagram of cross-section of leaf segment of
Bactris gasipaes. Note vascular bundles (vb), fiber
bundles (f), protruding vascular bundles (pvb).


250 urn

Figure 2-4. Diagram of cross-sections leaf segments of
Hyphaene petersiana. (A) Lamina section. Note bundle sheath
extensions (b) attached to vascular bundles (vb) and
hypodermis (h) on either side of mesophyll. (B) Cross
section of midvein showing two independent vascular bundles
(vb) each surrounded by own sclerotic fibers (f). The
expansion tissue (et) is above the midvein.




Figure 2-5. Diagram of cross-sections of leaf segments of
midveins. (A) Midvein with independent vascular bundles of
Nannorhops ritchiana. Note vascular bundles (vb) and fibers
(f). The expansion tissue )et) is above the midvein. (B)
Note xylem vessels (x) in common sclerotic shield of fibers
(sf) in Bactris gasipaes. The expansion tissue (et) is one
either side of the midvein.



Figure 2-6. Diagram of cross-section of leaf segment of
Livistona chinensis showing many independent vascular
bundles (vb) in midvein. Note position of fibers (f) and
expansion tissue (et).

250 urn

Figure 2-7. Diagram of large and branching transverse
veins in leaf segment of Lodoicea maldivica (10x).


0 id
0000 0.00001


provides useful characters (see Figs. 2-8 to 2-10). Certain

similar patterns have been observed in Sabal (Zona, 1990).

Segment shapes in the lamina. Figures 2-11 and 2-12

represent lamina shapes. Some leaves have upright "v" and

or inverted "A shaped lamina segments, while some have

more "T" shaped lamina segments.

Figure 2-8. Diagram of long and looping transverse veins
in leaf segment of Nypa fruticans (0lx).



Figure 2-9. Diagram of long and short transverse veins in
leaf segment of Thrinax morrissii (10x).


Figure 2-10. Diagram of vein patterns in leaf segment of
Kerriodoxa elegans. Note large branching transverse veins


Figure 2-11. Diagram of cross-section of leaf segment of
Licuala grandis. Note "V" shaped leaf section, expansion
tissue (et), and vascular bundle (vb).

250 urn

Figure 2-12. Diagram of cross section of leaf segment of
Socratea exhorriza. Note "T"shaped leaf blade and xylem
vessels :x) enclosed in common layer of sclerotic fibers

250 urn



The epicuticular wax characters used in this study were

compared to those used in Barthlott et al. (1998) in which

epicuticular waxes are characterized as films,

layers/crusts, and crystalloids.

Films are very thin. They represent the final layer of

the cuticle barely visible with the Scanning Electron

Microscope (SEM) (Barthlott et al., 1998). Layers and

crusts represent thick continuous coverings. Barthlott and

colleagues further described three different types of layers

and crusts-- smooth layers, crusts, and fissured layers.

Smooth layers are thin and have no prominent sculpturing.

They are distinguishable from films in SEM because they show

cracking. Crusts are continuous coverings with prominent

sculpturing. Often these crusts are very thick. Fissured

layers are usually thick, crusty coverings, fractured by

naturally occurring cracks (Barthlott et al., 1998).

Crystalloids represent distinct individual wax

projections. Barthlott et al. (1998) described five

categories of crystalloids: granules, plates and platelets,

rodlets, threads, and tubules. Granules are mostly

isodiametric, and often rounded crystalloids. Plates and

platelets represent flat crystalloids that project upward

differing in shape and size. Rodlets are massive structures

with a distinct longitudinal axis. Barthlott and associates

described four types of rodlets, which differ in diameter

and orientation. Threads are fine, long, crystalloids that

often form a felt-like covering. Tubules are hollow

crystalloids, with a terminal opening. Several types are

known, differing from each other in branch angle. Various

orientations and aggregations of these waxes are also

discussed in Barthlott et al. (1998).

The Streliztia-type of epicuticular wax is an

aggregation of rods. As noted by Barthlott (1983) and

discussed later, the form of these rods can vary in the

Streliztia-type wax, some being curled and others straight.

Others of the coalesced rods may form crusts or layers.

Some may form upright fences.

Barthlott and colleagues (1998) also discussed the

possibility that some leaf surfaces contain more that one

epicuticular wax type. Thus providing a firm foundation for

the classification of epicuticular wax structures. However,

the Barthlott classification, or any general-purpose

classification, necessarily requires modification, when

applied to a particular plant group, as discussed below.


Many of the genera assessed in the phylogenetic

analysis of Arecaceae by Uhl et al. (1995) were collected,

observed and used in this investigation. The epicuticular

wax samples were taken from plants cultivated at the

Fairchild Tropical Garden in Miami, Florida. A 15 cm leaf

segment was cut from healthy leaves, flattened, and air

dried. Immature leaves were not used because they may not

have developed the mature form of epicuticular wax

structures and patterns. For consistency only the adaxial

surface was viewed using the SEM. Each specimen was

labeled, including the name, date, location, and the

Fairchild Tropical Garden accession number. Voucher

specimens were made of those plants not already vouchered

and deposited in the herbarium of Fairchild Tropical Garden.

Because the exact chemical composition of the epicuticular

wax of each leaf was not known, leaves were air-dried. It

was thought that excessive heat might damage the

epicuticular wax structures (Reed, 1982). Other available

methods included critical point drying and the use of

hexamethyldisilizane (HMDA) (Dykstra, 1993). With both of

these methods it is important to keep the specimen as cool

as possible (Reed, 1982). Critical point drying involves a

pressurized chamber filled with cold carbon dioxide. This

process may obscure the wax structures since the alcohol and

organic solvents used may interfere with the epicuticular

wax structures. HMDA is often considered to be the

simplest method for preparation of material for the SEM; it

allows the quick use of fresh material. However, here again

the organic solvents may dissolve or alter epicuticular wax

structures. Hence, air drying is considered to be the best

method for this investigation.

After specimens were air dried, one centimeter segments

were placed adaxiall side up) onto studs, gold coated using

the Eiko IB4 sputter coaster, and placed into the Hitachi

4000 Field Emission Scanning Electron Microscope. The

scope's water chiller chilled the diffusion chamber to

minimize heating that could possibly damage the specimen.

The accelerating voltage of the scope was 6.00 kv.

Epicuticular Wax Characters

The epicuticular wax characters used in this study are

character 29-37 listed in Table 2-3. These characters

differ somewhat from those described by Barthlott et al.

(1998). Although the Barthlott system was taken into

consideration, it was necessary to modify the categories of

Barthlott et al., based on the patterns of variation in

epicuticular waxes observed in this study.

Many of the epicuticular wax characters listed on Table

2-3 can occur on the same leaf surface. They vary

independently, with the exception of fissuredd layers" (a

type of layered epicuticular wax) and curled coalesced rods

(a type of coalesced rods). All characters are treated as

unordered. Character states are qualitatively different,

and are coded as presence/absence features. Polarity is

inferred based on rooting the cladograms resulting from the

cladistic analysis with Nypa. Nypa was hypothesized to be

the sister group of all other palms by Uhl et al. (1995),

and therefore, is suitable outgroup for this study. The

nine epicuticular wax characters used in this study are

described below (see also Table 2-3).

Epicuticular wax crystalloids. There are five different

kinds of epicuticular wax crystalloid structures:

platelets, granules, membranous platelets, coalesced rods,

and curled coalesced rods.

Smooth epicuticular wax layer. This layer represents a

surface that is relatively smooth though may show some

artificial cracking and or rough surfaces. No crystalloids

project from it. This smooth surface differs from that

described by Barthlott et al. (1998) in that films and

smooth layers are distinguished in their study. Barthlott

et al. (1998) separated them based on thickness and degree

of smoothness, but I found this distinction difficult to

make. Examples of smooth surfaces are given in Figures 3-1

A and B. Crusts/layers of epicuticular wax. This wax type

Figure 3-1. A) Socratea exorhiza, note smooth epicutiular
wax layer. B) Licuala grandis, note smooth epicuticular wax



represents a covering that is typically thick and

continuous. There are two types of crusts/layers, i.e.,

fissured layers and crusts that differ in surface

sculpturing. Examples of crust/layers are shown in Figures

3-2 B & 3-3 A and B. Figure 3-2 B represents crusts of

coalesced epicuticular wax rods. Figure 3-3 A and B

represent fissured layers of epicuticular wax. Fissured

layers are formed when thick continuous smooth coverings

break and separate into flat sheets (Fig. 3-3 A and B).

Coalesced epicuticular wax rods. Coalesced rods represent

rods that have fused together. This fusion of rods often

results in the formation of thick crusts. Often massive

amounts of wax are present. Sometimes the fused rods form

upright barriers as in Figure 3-4. Barthlott et al. (1998)

use the term rodlets for this type of wax and described four

different sub-types. Subdivisions of this category were not

distinguished in this study, with the exception of curled,

coalesced rods (Fig. 3-2 B). These rods are fused and

curled in contrast to straight, upright fused rods. Curled

rods may also be scattered over the cuticular surface (see

Fig. 3-2 A).

Granules. These crystalloids are rounded structures that

project from the cuticular surface. They are typically

scattered (Fig. 3-5 A and B). Barthlott et al. (1998)

Figure 3-2. (A) Phoenix acaulis, note scattered curled
coalesced epicuticular wax rods. (B)Copernicia prunifera,
note coalesced epicuticular wax rods.



Figure 3-3. (A) Allagoptera arenaria, note fissured
layers. (B) Acoelorraphe wrightii, fissured layers.



Figure 3-4. (A) Latania loddigesii, note coalesced
epicuticular wax rods sometimes forming an upright structure
around stomata. (B) Nannorrhops ritchiana. Note coalesced
rods coalesced sometimes forming upright barriers.


Figure 3-5. (A) Rhapis excelsa, note granules (g) and
platelets (p). (B) Lodoicea maldivica note granules.



suggest that this crystalloid type is often mistaken as an


Platelets. Platelets are flat crystalloids that project

from the cuticular surface. Barthlott et al. (1998)

described several different kinds of plates and platelets on

the basis of size, shape and orientation. The variation

observed in this study did not coincide with these

delimitations. Thus, all flat structures that

project from the surface here are considered to be platelets

(Fig. 3-6 B).

Membranous platelets. These structures differ from typical

platelets in that they are thinner and appear flimsy.

Barthlott et al. (1998) considered membranous platelets to

be interconnected and to protrude at acute angles. They are

often found together with other kinds of crystalloids (Fig.

3-6 A).

Scattered epicuticular wax crystalloids. This pattern often

represents various kinds of crystalloid structures scattered

across a leaf surface (Fig. 3-5 B).

On the basis of my observations of the patterns of

variation within the Arecaceae, using the above delimited

categories of wax types, the characters and character states

listed in Table 2-3 are suggested to be of potential

phylogenetic significance.

Figure 3- 6. (A) Calyptronoma occidentalis, note membranous
platelets. (B) Pinanga cunnani, note platelets.




Cladistic Analysis Based on Anatomical and
Micromorphological data.

The taxa used in my analysis of anatomical and

micromorphological data are listed in Table 2-2. Many of

these same taxa were also used by Uhl et al. (1995) in their

cladistic analysis. The various characters and character

states of each taxon are tabulated in the data matrix shown

in Table 4-1 (and characters 1-43 in this matrix represent

anatomical and micromorphological features). A preliminary

heuristic search was done using Hennig86 (Farris, 1989) that

produced trees very similar to those produced by PAUP, as

discussed below. A heuristic search was performed using the

Beta test version of PAUP* 4.Obl for the Macintosh computer

(Swofford, 1997). All multistate characters were unordered

and all characters were equally weighted. Forty of the

forty three characters were phylogenetically informative.

The tree-bisection-reconnection (TBR) branch swapping

algorithm was used on trees generated from 500 random

addition replicates. This search produced eight most

parsimonious trees, with a length of 190, a consistency

index (CI) of 0.29, and a retention index (RI) of 0.56. The

trees were rooted using Nypa as a functional outgroup, as

Characters 1-43 represent anatomical/micromorphological
characters; characters 44-80 represent Uhl et al. (1995)
morphological characters; characters 81-223 represent Uhl et al.
(1995) molecular characters.
Sypa fruticana
oooOoil:,-iOOCooooo 1110001010100011111001 0101010001100 0111
Bactris gazipaox
01000C?11100 10 01001?00? 7o?11C1100000071041??000110320?0???1003?7327??:00077.?????
...5 ~ ~- -' 5'. .. .. .. . .. .. . .. .. .

Nannorrhcps ritchiaaa
1OO COOC1001 3200601001100001 000001100000001.010110-0011-
11OOOOOO1 0010001011~1010010001101111110000101 01111110111011100111 0111111O0 111010010
111C00 n10o0011.111011011100011111101011000000010001000011101010110111
Latania 1oddigwsli
12100001111000321060100111000100100100010000000000100100 2001111100300101002000110011101
0010011 01111100010010111111110101 01001 0101111110101110 0100111 000 1000111011 11011
10011111CC1100 0000 1000 100 00111010 110 111
Socratea exhorrIza
0011000.1100010OO??01c00OO 7?1100010000.00011303?1011003201010111003.0070??0?010??????7?
"~7? >733?37"777777'733~75'7'?33 ;?? 7?573777'77333?333?3??
Pinanga curranii

.. ..... ... ... . .. .. .5 ? .. . ... .. ... ...'. .... ..... ..
Hyphaene petersiana
1200100001000103210060100111000100100010000000 0000110011001111100300100102000110011101
0010001101111111000010001011110111010100111011101111010111010011011100001 00001111111011011
Livistona chinenais
OC.1001000 .1.1 301 00110 0011 0110C 0000 00010001 10-0010-
-11.CO0001100010 001 010 1>0100011011111 01010001101 01110100010 1011110>10011100110
Dzycphloxus olirifoz.Ji
??oc??o 9ooo????? ????????? ?? ?????????????????????????? ???????????????????? ??????????????
7 0.07??7????7?73?7 7177??3 3?70?? ?33?37777>73?.7.??7?>77777?37777

Dictyospema album
00-110000. 1 ". 010 31 00000 1 10001C01020??100111?2?01000-
IO^? O?? 000?????????????????????????????? ???????????????????????????????????????????????
???3';7??"?*?7 '"?? ?7'3?7?">*?7?????3?375"73"5???? 77?3??3'1"????????????7? 3??3??>7:?357'?
.... ... .00 0... . .
Calyptronoma occidentfalis
00100001i000111 70??010010000?0200011000010000??7700110320?010011000?00??1?0000?????????
?????7???7??777???3 -s3?7s?3?3????7?3333755??3

Coccothrinax iraguaa
3000012 00010001110110100010011101111100010100100110O1101000110110101110011111001101110
ca7-8 conaainnus
0001 -1- 110 010 11 0 1 10 01 4100111421?010011OO1 10??0771??01?????????

2. 5. .5 .. 55 5 -5 5'5 5 55 5 '. -- -5 5
Thrinax swriaxii
11101001110001010C10040100000 1 0191100900000000000000010000-0020-0-
300000011000100011101101011Ooc111110001000010011010001111100010111110101 0 1001101110
Chta' zcp& humilis

Acoelozraphe wxightii
11100001 000010111101101101001101100101100000001001100001110101010C101


TABLE 4-1 continued.
Rhapis excelsa
Dypsia cabadae

???????? ,7?? ????????'?????????????????????????????????7?????.
Ravrna hildbrzandtii
10110110ooo iiooiooiooo iioiooiiiiioooioioilllllOl011110100101011 110001iiii0 oli ooiocoo01111
Azrenga microcarpa

Licuala grandiJ
?1111 00111001101131001010000071100010000010000001000010010-0010-
Lodoicea maldivica
001COC110111111000001010111110111110100101111111 1011101001101110000100001111111011011
Pasudophoenix aargentii
11020011001 001110100100011011111111000101011101101110101001010 11111001111110110
Karriodoxa a7egans
000001101111111 C00010101111110111011100011011111110001110100110M111000100001111 111011011
1i0001111iii1 011000000010001100011101010110111
Allagoptza azrmnaria
00110001081001011100080100000?00101100000100104110000110320001011100020 0000000000110010
00101?1011111111011000101011111101110101001010111111100011111001101011 000000001111111101
Clambeyronia macrocarpa
? n'">?? ????????????????????????????????????????????????????????????'???????? ???';';'''7""7
????????????? ?????7">""7S7>7'77'>'55'7 7 77p7p???? ?????7777??? ??????????????????
PhoenIx acauli.
Copenicia prunifera
Sabal palmetto
11 0000001110001q00111011010001101111111100010000101110111010100111011110110001111100110
Sezrnoa zopena
Mhapidaphylltm histrix
100000011000100110101o00011011111110001 0011110101110100001010111110100011111oollol

suggested in the analysis of Uhl et al. (1995). The strict

consensus tree (Fig. 4-1) shows a clade containing

Nannorrhops + Hyphaene + Latania + Lodoicea + Sabal + Rhapis

+ Phoenix + Copernicia; Coccothrinax + Kerriodoxa + Licuala;

Dictyosperma + Pseudophoenix + Allagoptera; Socratea +

Calamus + Ravenea + Arenga; and Drymophloeus + Dypsis +

Calyptronoma. In addition, the Coryphoideae form a clade,

with Thrinax sister to all other members of the Coryphoid

clade included in the analysis. As in a representative tree

(Fig. 4-2) the Nannorrhops + Hyphaene + Latania + Lodoicea +

Sabal + Rhapis + Phoenix + Copernicia clade share the

following characteristics: prominent midribs with two or

more vascular bundles (character # 27), midrib vascular

bundles enclosed in a common layer of fibers (character

#28), and large transverse veins (character #39). The

members of Coccothrinax + Kerriodoxa + Licuala clade are

united by the lack of epicuticular wax crystalloids

(character #32). In some trees Livistona + Serenoa +

Acoelerraphe + Chamaerops form a clade based on character

#27 (midrib with two or more vascular bundles).

Rhapidophyllum is sister to this clade. The Coryphoideae

share the following derived characters: induplicate

plication (character #1), palmate leaves (character #2),

presence of a hastula (character #5), and fiber bundles near

the adaxial surface (character #19). Dictyosperma,

Figure 4-1. Strict consensus of eight most parsimonious
trees resulting from analysis of anatomical and
micromorphological data (characters 1-43). Full names of
each taxon are in Table 4-1. Decay values given above the


Pseudophoenix, and Allagoptera all have a one layered

hypodermis (character #9) and adaxial bundles attached to

the surface (character #18). The monophyly of the group

containing Drymophloeus, Dypsis, and Calyptronoma is

supported by the inconspicuous expansion tissue (character

#25) and absence of a distinct palisade layer (character

#13), and Socratea, Calamus, Ravenea, and Arenga all have

smooth epicuticular wax (character #31). Almost none of

these clades is strongly supported (see Fig.4-1).

The pattern of character state changes on the most

parsimonious trees resulting from the analysis of anatomical

and micromorphological characters were explored using

MacClade version 3.1 (Maddison & Maddison, 1992).

Noteworthy character states functioning as synapomorphies in

these trees include a prominent midvein with two or more

vascular bundles (character #27), prominent midrib enclosed

in common layer of fibers (character #28), coalesced

epicuticular wax rods (character #29), smooth epicuticular

wax (character #31), scattered epicuticular wax crystalloids

(character #32-2), crystalloids covering the entire surface

(character #32-0), absence of crystalloids (character #32-

1), crusts/layers of epicuticular wax (character #33), and

fissured layers (character #35). Character #27 helps define

two clades; both are in the Coryphoideae (see Fig. 4.3).

Character #28 helps define the same clades but its value is

Figure 4-2. Representative most parsimonious tree from
analysis of anatomical and micromorphological data. Length
190. CI = 0.29, RI = 0.56. The letters represent the
following characters a) 3-1, 14-1, 22-2, 32-2; b) 4-0, 17-
1, 21-1, 22-0; c) 5-0, 20-0, 41-1, 42-1, 43-0; d) 11-0, 40-
1; e) 14-0, 3-0, 39-0, 13-0, f) 16-0; g) 10-0, 29-1; h) 5-
0, 11-0, 12-0, 22-7, 32-2, 36-0, 38-1, 43-0; i) 8-0, 9-0,
19-2; j) 31-1, 32-1, 40-1, 41-1; k) 2-2, 4-0, 22-6; 1) 11-
0, 12-0, 17-1, 18-0, 34-1, 36-0; m) 42-0; n) 22-3, 33-1,
40-1; 0) 27-1, 30-0, 39-1, p) 2-0, 5-0, 19-2, 26-1, 32-2;
q) 11-1, 12-1; r) 8-0, 22-6, 32-2, 34-1, 41-1; s) 4-0, 10-
0, 11-1, 17-1, 38-1, 39-1, 40-1, 42-0; t) 9-0, 16-0; u) 17-
1; v) 32-1; w) 13-1, 33-0, 35-0; x) 2-2, 1-0, 20-1, 22-3;
y) 12-1, 14-0, 29-1, 41-1; z) 16-0, 39-1; aa) 13-1, 21-1,
22-0, 23-1, 24-0; bb) 11-1, 38-1, 42-0; cc) 20-1; dd) 27-1;
ee) 2-2, 16-0, 18-2, 22-0, 41-1, ff) no unambiguous
characters; gg) 13-1, 35-0, 33-0; hh) 22-4, 4-0; ii)l-l,
18-3, 42-1; jj) 18-3, 19-1, 41-1; kk) 4-0, 7-1, 15-1; 11)
10-0, 17-1, 22-8, 42-1; mm) 8-0, 20-1; nn) 9-0, 18-1; 00oo)
16-1, 32-0; pp) 25-1; qq) 4-0, 39-1; rr) 5-1, 21-1; ss) 1-
1, 41-1; tt)5-1, 21-1; uu)17-1; vv) 31-1; ww) 1-0, 10-0,
41-1; xx) 32-1; yy) no unambiguous characters; zz)36-0 ; A)
4-0, 16-1, 17-1, 37-1, 42-1; B) 13-1, 25-1; C) 8-1, 9-1,
22-1; D) 21-1, 24-1, 37-1, 42-1; E) 6-1, 18-2, 34-1; F) 4-
1; G) 3-1, 14-1, 22-2, 32-2, 36-1; H) 33-1, 35-1. Full
names of each taxon are in Table 4-1.


Figure 4-3. Representative most parsimonious tree from
analysis of anatomical and micromorphological data.
Character #27. Midrib not prominent, lacking two or more
vascular bundles as indicated by white lines; midrib
prominent with two or more independent vascular bundles
represented by black lines. Full names of each taxon are in
Table 4-1.



I '--in UCUALA