Small in a big world: Ecology of leaf-litter geckos in new world tropical forests

Abstract

We studied the ecology of four species of closely related leaf litter geckos, Coleodactylus amazonicus, C. septentrionalis, Lepidoblepharis xanthostigma, and Pseudogonatodes guianensis in tropical rainforests of Brazil and Nicaragua. All are found in leaf litter of undisturbed tropical forest where mean hourly surface temperatures vary from 23.5-29.1 C. Surface temperatures, where individual C. amazonicus were found, averaged 27.4 C and air averaged 29.9 C. Coleodactylus amazonicus was the smallest species and L. xanthostigma was the largest. The latter was the most different morphologically as well. Tail loss rates varied from 45.5-81.8% among species. All four species ate very small prey items, largely springtails, homopterans, termites, small insect larvae, and spiders. Nevertheless, considerable differences existed among species. Some variation existed among populations of C. amazonicus. Prey size was correlated with lizard SVL within and among species. All four species are typically the smallest species in their respective lizard assemblages. Small body size may have consequences for predation. Partially due to small body size, these lizards are vulnerable to extirpation resulting from effects of tree removal on thermal attributes of their leaf litter environment.

Full text

Herpetological Monographs, 19, 2005, 137–152
Ó2005 by The Herpetologists’ League, Inc.
SMALL IN A BIG WORLD: ECOLOGY OF LEAF-LITTER
GECKOS IN NEW WORLD TROPICAL FORESTS
LAURIE J. VITT
1,5
,SHAWN S. SARTORIUS
2
,TERESA CRISTINA S. AVILA-PIRES
3
,
PETER A. ZANI
4
,AND MARIA CRISTINA ESPO
´SITO
3
1
Sam Noble Oklahoma Museum of Natural History and Department of Zoology,
University of Oklahoma, Norman, OK 73072, USA
2
U.S. Fish and Wildlife Service, Ecological Services, Billings Sub-Office,
2900 4th Ave. N., Billings, MT 59101, USA
3
Departamento de Zoologia, Museu Paraense Emı
´lio Goeldi/CNPq/MCT,
Caixa Postal 399, 66017-970 Bele
´m, Para
´, Brasil
4
Department of Kinesiology and Applied Physiology,
University of Colorado, Boulder, CO 80309, USA
ABSTRACT: We studied the ecology of four species of closely related leaf litter geckos, Coleodactylus
amazonicus,C. septentrionalis,Lepidoblepharis xanthostigma, and Pseudogonatodes guianensis in tropical
rainforests of Brazil and Nicaragua. All are found in leaf litter of undisturbed tropical forest where mean hourly
surface temperatures vary from 23.5–29.1 C. Surface temperatures, where individual C. amazonicus were
found, averaged 27.4 C and air averaged 29.9 C. Coleodactylus amazonicus was the smallest species and
L. xanthostigma was the largest. The latter was the most different morphologically as well. Tail loss rates varied
from 45.5–81.8% among species. All four species ate very small prey items, largely springtails, homopterans,
termites, small insect larvae, and spiders. Nevertheless, considerable differences existed among species. Some
variation existed among populations of C. amazonicus. Prey size was correlated with lizard SVL within and
among species. All four species are typically the smallest species in their respective lizard assemblages. Small
body size may have consequences for predation. Partially due to small body size, these lizards are vulnerable to
extirpation resulting from effects of tree removal on thermal attributes of their leaf litter environment.
Key words: Squamata; Gekkonidae; Coleodactylus;Lepidoblepharus;Pseudogonatodes; Lizard ecology;
Rainforest.
New World tropical forests are well known
for their biotic diversity (Wilson, 1988) and the
complexity of potential species interactions
(Erwin, 1983). Aside from their remarkably di-
verse vegetation (Valencia et al., 1994), these
forests contain a striking diversity of animal
species, including most major vertebrate
groups (Azevedo-Ramos and Gallati, 2001;
Dixon and Soini, 1975; Janzen, 1993; Oren,
2001; Vogt et al., 2001). Both Caribbean low-
land forest and Amazonian lowland rainforests
share a mat of leaf litter covering the ground
within mature forest, a microhabitat type
that contains not only numerous invertebrate
species, but many small frogs and lizards
(Allmon, 1991; Caldwell and Vitt, 1999; Duell-
man, 1987, 1990; Duellman and Mendelson,
1995; Hoogmoed, 1973; Lieberman, 1986;
Scott, 1976; Vitt and Caldwell, 1994). Among
the smallest vertebrates in these tropical
forests are gekkonid lizards in the clade that
includes the genera Coleodactylus,Pseudogo-
natodes, and Lepidoblepharis, all of which live
exclusively in leaf litter. Moreover, these are
typically the smallest lizard species in their
respective assemblages (e.g., Duellman, 1978,
1987; Lieberman, 1986; Vitt and Zani, 1996a,
1998a,b; Vitt et al., 1999). Because they are
smaller than many invertebrates, these geckos
could be competitors with or prey of many
invertebrates (see Vitt, 2000). Also, because
many frog and lizard species eat nearly any-
thing small enough to fit in their mouths, these
tiny geckos are at risk of predation by other
predacious terrestrial vertebrates and birds.
We examine in detail the ecology of four
species representing all three genera. One
species, Coleodactylus amazonicus, was stud-
ied at six localities in the northern, central, and
western Amazon, so we provide some insight
into geographic variation in the ecology of this
species, recognizing that some of these pop-
ulations may be distinct taxa (M. T. Rodrigues,
personal communication). We describe micro-
habitat use, morphology, tail loss rates, activity,
5
CORRESPONDENCE: e-mail, vitt@ou.edu
137

thermal ecology, and diets. We comment on
some of the many consequences of small body
size in extremely complex and diverse tropical
lowland forests. Finally, we suggest that these
lizards are at high risk of local extirpation
because their ecological traits make them vul-
nerable to consequences of changes in land use.
MATERIALS AND METHODS
Coleodactylus amazonicus was studied at the
following localities: Rondo
ˆnia, Brazil (38229S
latitude, 518519W longitude) in 1985 during
the peak of the dry season (hereafter Rondo
ˆnia
85); transitional forest in southern Roraima,
Brazil (2809N latitude, 628509W longitude) in
1993 during the wet season (hereafter, Ror-
aima); the Curua
´-Una region of central Para
´,
Brazil (38319S latitude, 598549W longitude)
in 1995 during the wet season; the Rio Ituxi in
western Amazonas, Brazil (88209S latitude,
658439W longitude) in 1997 during the wet
season; the Rio Formoso in Rondo
ˆnia (108199
S latitude, 648339W longitude) in early 1999
during wet season (hereafter Rondo
ˆnia 99),
and; southeast of Manaus in Amazonas, Brazil
(38209S latitude, 59849W longitude) in
late 1999 during the wet season (hereafter,
Solim~
oes). Coleodactylus septentrionalis was
studied concurrently with C. amazonicus in
transitional forest in southern Roraima, Brazil
in 1993 during the wet season. Lepidoblepharis
xanthostigma was studied in Caribbean low-
land forest in Rio San Juan Province, Nicar-
agua (11839N latitude, 858409W longitude) in
dry season of 1993. Pseudogonatodes guianen-
sis was studied near the Rio Jurua in Acre,
Brazil (88159S latitude, 728469W longitude)
during wet season of 1996. We emphasize that
two species occurred together in only one
locality (Roraima). Thus our comparisons
among species and populations are not in-
tended to imply that these species and/or
populations interact in any way.
Because these geckos were studied concur-
rently with sympatric species of tropical forest
lizards, we recorded habitat type and micro-
habitat data for every individual of all species.
Consequently, numerous habitats not contain-
ing these geckos were searched. We present
only those data pertinent to these particular
species. To collect data on activity and micro-
habitat use, we conducted haphazard searches
in the forest from early morning until near
dark. This method has proven effective in
lowland forest habitats (e.g., Vitt et al., 2000).
For each lizard observed, we recorded the
habitat type and microhabitat in which the
lizard was first observed. Because of the small
body size of these lizards, we did not take body
temperatures (T
b
). For some lizards, we re-
corded substrate temperatures (T
ss
) at the
exact spot where the lizard was found along
with air temperatures (T
a
) to 0.2 C with Miller-
Weber rapid-register thermometers. For two
populations of C. amazonicus and a population
of P. guianensis, we sampled temperatures in
leaf litter microhabitats where these lizards
were found using electronic temperature
devices. We include those data to characterize
thermal conditions in microhabitats used by
the lizards. Temperatures were recorded at
five-minute intervals 24 h per day using HOBO
or TidBit electronic temperature recording de-
vices supplied by OnSet Computer Company
at two localities (Rio Ituxi and Rio Jurua).
These devices have been shown to produce
temperature profiles similar to copper models
for lizards of relatively small body size (Vitt and
Sartorius, 1999; Shine and Kearny, 2001) and
thus can be considered accurate estimators of
operative temperatures (Hertz et al., 1993). A
total of 26 days were sampled at the Rio Ituxi
and 30 days at the Rio Jurua. At the Curua
´-Una
site, we used an Omega OM-550 data logger
with type-T thermocouples to record leaf litter
temperatures at 30-minute intervals (see Vitt
et al., 1997afor details). A total of 24 days were
sampled at this site. We restrict the pre-
sentation of microhabitat temperature data to
those hours during which the geckos were
observed active. For perspective, we also plot
temperature data taken in a forest treefall at
one of the sites (Curua
´-Una). For this paper,
we combined temperature data for all days at
each site and calculated hourly means.
All captured lizards were returned to our
field laboratories within 2 h of capture, killed
by immersion in Chlorotone following ap-
proved protocols (Anonymous, 1987), and
measured for the following morphological
variables with vernier or electronic calipers:
snout–vent length (SVL), tail base (original,
unregenerated portion), length of regenerated
tail portion, if any, head width, length, and
height, body width and height, and hindleg
138 HERPETOLOGICAL MONOGRAPHS [No. 19

length. Measurements were to 0.1 mm. Total
mass was taken with Pesola spring scales (0.1
g) or Acculab field balances (0.01 g), depend-
ing upon locality. Lizards were then fixed in
10% formalin and later transferred to 70%
ethanol for permanent storage. Prior to trans-
fer to alcohol, lizards were dissected, stomachs
removed and either immediately analyzed or
placed in 70% ethanol for later analysis, and
reproductive organs were examined.
In addition to simply comparing SVL among
species and populations, we used a Principal
Components Analysis (PCA) to examine po-
tential differences in bauplan. Because all
morphological variables are correlated with
lizard size, we first performed regression on
log-transformed variables against log trans-
formed SVL for all species pooled. We then
calculated the residuals from those regressions
to adjust for species/population differences in
lizard size, and used the residuals in the PCA.
For lizards with broken or regenerated tails, we
substituted estimated tail lengths (see below).
We compared factor scores from the PCA
among species/populations with ANOVAs.
We calculated tail loss rates for each species
by dividing the number of lizards with missing
or regenerated tails by the total number of
lizards in sample. We use these only as
indicators of potential risk of predation. We
have no data on condition of tails for lizards
that were predated (see Schoener, 1979;
Schoener and Schoener, 1980). For lizards
with complete tails (no indication that they had
ever been broken), we regressed tail length on
SVL and, if significant linear relationships
existed, we used the equation for the tail to
SVL relationship to estimate original tail
lengths of lizards with missing or regenerated
tails. Using these estimates of original tail
length, we were then able to calculate relative
position at which tail break had occurred and
relative length of regenerated tail as compared
to the original.
To examine diets, we opened stomachs of
sampled lizards, carefully separated prey
items, identified them to family or the next
highest possible taxonomic category, counted
them, and measured each item for length and
width to 0.01 mm, using electronic calipers
or an ocular micrometer in a dissecting micro-
scope. Prey items in lizard stomachs are
compressed with limbs and wings pressed
against the body approximating the shape of
a prolate spheroid. Hence, we estimated
volumes for individual prey items with the
formula:
V¼4=3pðprey length=2Þðprey width=2Þ2
We then grouped prey items into the
following broad categories for further analysis:
ants, beetles, centipedes, earthworms, embiop-
terans, flies, hemipterans, homopterans, insect
larvae, isopods, lepidopterans, lizard shed skin,
grasshoppers & crickets, millipedes, mites,
non-anthymenopterans, opiliones,pseudoscor-
pions, psocopterans, roaches, snails, spiders,
springtails, termites, thysanopterans, ticks,
vertebrates, and walking sticks. Ants were
considered different from other hymenopter-
ans because of the distinct wingless morphol-
ogy of workers, their surface activity, and their
high relative abundance. Diet data were
analyzed with BugRun 1.7, a program based
in 4
th
DimensionÒ. Prey measurements and
lizard SVL were log
10
transformed for analyses.
The program produces dietary tables summa-
rizing the diet, calculates niche breadths, and
produces additional data sets for other analyses.
Complete diets were summarized for each
species or population and proportional utiliza-
tions of prey types were calculated for numer-
ical and volumetric data by dividing values
for each prey type by column totals and
multiplying by 100 to convert to percentages.
Prey niche breadths were calculated as the
inverse of Simpson’s (1949) measure (see
Pianka, 1973, 1986).
B¼1X
n
i¼1
p2
i
,
Niche breadth values vary from 1 to nwith
low values indicating reliance on one or a few
prey types and high numbers indicating
relatively even use of numerous prey types.
Another data set produced by BugRun 1.7
includes means of prey width, length, and
volume for each individual lizard. These data
were log
10
transformed to normalize the
distributions, merged with the lizard morphol-
ogy data set, and regressed with log
10
SVL
to determine if lizard body size influences
the size of prey items eaten. We used linear
regression to test the association between
2005] HERPETOLOGICAL MONOGRAPHS 139

mean prey size and mean lizard SVL among
species/populations. Because prey size within
species/populations was correlated with lizard
SVL, we also performed an ANCOVA to test
the hypothesis that prey size and lizard size are
not associated in the same manner among
species/populations.
BugRun 1.7 also produces a consumer-
resource matrix with lizard species as rows
and resources as columns. We calculated
overlaps in prey use among the gecko species
and populations and compared those overlaps
with overlaps generated by two different
randomization methods (see Winemiller and
Pianka, 1990) making no assumptions about
potential differences among species or pop-
ulations in resource availability. Overlaps were
calculated with the following formula:
jk ¼X
n
i¼1
gij X
n
i¼1
gik
ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi
X
n
i¼1
g2
ij X
n
i¼1
g2
ik
s
where symbols are the same as above with j
and krepresenting lizard species (Pianka,
1973, 1986).
Briefly, the analysis computes proportional
utilizations (p
i
), then computes electivities (e
i
)
normalized to vary from 0–1, and finally
calculates the geometric means (g
i
)ofp
i
and
e
i
to minimize biases associated with p
i
and e
i
data. The g
i
were then used to calculate dietary
overlaps among species. A new set of overlaps
was calculated in the same way by first
randomizing the addresses in the matrix of
resource data for each lizard species such that
the number of resources and niche breadths
remained the same. Another set of overlaps was
calculated the same way but resource ad-
dresses with values of zero were not shuffled.
Each of these was calculated 1000 times. If
95% of the overlaps resulting from the random-
ization procedure were greater than observed
overlaps, we concluded that species differ sig-
nificantly in diets. If less than 95% of the
overlaps produced by the randomization pro-
cedure were greater than observed overlaps,
we conclude that the lizards randomly select
from a set of prey items eaten by all leaf litter
geckos.
The Macintosh versions of Statview 4.5 was
used for statistical analyses. Voucher speci-
mens have been deposited in the following
museums: Museu de Zoologia da Universidad
de Sa
˜o Paulo (MZUSP) in Sa
˜o Paulo, Brazil,
the Museu Paraense Emı
´lio Goeldi (MPEG)
in Bele
´m, Brazil, the National Museum of
Nicaragua in Managua, Nicaragua, and the
Sam Noble Oklahoma Museum of Natural
History (OMNH) in the United States.
RESULTS
Habitat and Microhabitat Use
and Thermal Ecology
Nearly all individuals of the four species
were found in leaf litter. Among 277 C.
amazonicus, 274 were in leaf litter, one was
on open ground, one was on a fallen branch,
and one was under a piece of wood. Among
53 C. septentrionalis, 52 were in leaf litter and
one was on open ground surrounded by leaf
litter. All 11 L. xanthostigma were in leaf litter
and 33 of 34 P. guianensis were in leaf litter.
The other one was on open ground surrounded
by leaf litter. Most individuals of the four
FIG. 1.—Habitat occurrence for four species of Neo-
tropical leaf litter geckos.
140 HERPETOLOGICAL MONOGRAPHS [No. 19

species were found in one of several primary
forest habitats, but C. amazonicus was found
in a wider variety of forest patches (Fig. 1),
sometimes using lightly disturbed primary for-
est as long as leaf litter and shade were present.
Coleodactylus septentrionalis was found for the
most part in terra firme forest (18forest) and at
the edge of swamps in forest. Lepidoblepharis
xanthostigma was found only in terra firme
forest. Pseudogonatodes guianensis was found
in both undisturbed terra firme forest and
undisturbed low primary forest.
These geckos were found active only during
the day. Among the three species for which we
had adequate data, C. amazonicus and P.
guianensis were active throughout the day with
greater numbers of C. amazonicus observed
about mid-day (Fig. 2). Coleodactylus septen-
trionalis were active throughout the day, but
activity appeared to peak just before mid-day
and again late in afternoon. Lizards were about
equally likely to be active on cloudy as on
sunny days but appeared to avoid direct
exposure to sunlight (Table 1). T
ss
and T
a
taken at the point where 50 individual C.
amazonicus were captured averaged 27.4 6
0.21 C and 29.9 60.18 C, respectively. We
make the assumption that T
ss
approximates
lizard T
b
because the lizards are very small and
thus have little thermal inertia, and because
lizards were rarely exposed to sun which might
allow them to gain heat.
Mean hourly temperatures in leaf litter
varied from 24.0 60.02 to 26.0 60.03 C at
the Rio Ituxi, 23.5 60.03 to 25.3 60.03 C
at the Rio Jurua, and 23.6 60.09 to 29.1 6
1.11 C at the Curua
´-Una site (Fig. 3). Because
the number of temperatures used to calculate
hourly means was large (partially as a result of
many samples and partially a result of com-
bining days), SE were extremely small. Plots of
all temperatures recorded (not shown) reveal
that temperatures below 27 C were available in
leaf litter throughout the day. In sharp
contrast, hourly means of leaf litter in a forest
treefall at the Curua
´-Una site exceeded 27 C
for six hours (1000–1600 h; Fig. 3).
FIG. 2.—Activity cycle for three common species of
Neotropical leaf litter geckos. All populations of C.
amazonicus are combined.
TABLE 1.—Percent of leaf litter geckos active on sunny
versus cloudy days and relative exposure of lizards to
filtered sun, shade, or sun.
Species
Cloud cover Lizard exposure
Cloudy Sunny Filtered sun Shade Sun
C. amazonicus 56.4 43.6 28.7 68.0 3.3
C. septentrionalis 35.8 64.2 53.7 44.4 1.9
P. guianensis 64.7 35.3 20.6 79.4 0.0
FIG. 3.—Hourly mean temperatures in three rainforest
leaf litter microhabitats occupied by leaf litter geckos.
Temperatures in a forest treefall are also shown for
perspective. Most SEs are less than the size of points
shown but considerable variation does exist.
2005] HERPETOLOGICAL MONOGRAPHS 141

Lizard Size and Morphology
Superficially, these small, closely related
geckos look alike but can be distinguished at
the generic level by distinct differences in toe
morphology (Fig. 4; Kluge, 1995). Among the
species we studied, C. amazonicus was the
smallest whereas L. xanthostigma was the
largest (Fig. 5). Hatchlings of C. amazonicus
were as small as 11.6 mm SVL and those of
P. guianensis were as small as 14.4 mm SVL.
We did not collect hatchlings of the other spe-
cies. Morphology varied considerably among
species as well (Table 2).
PCA on eight size-adjusted morphological
variables produced four factors accounting for
65.0% of the variation in bauplan. Factor I
described a gradient weighted by relative mass
and relative head size accounting for 23.1% of
morphological variation (Fig. 6; Table 3).
Factor II described a gradient weighted by
relative body width and relative tail length
(negative loading) accounting for 19.1% of
morphological variation. Factor III described
a gradient based on relative hindleg length
accounting for 13.1% of morphological varia-
tion. Factor IV described a gradient based on
relative body height accounting for 10.7% of
morphological variation. ANOVAs on factor
scores revealed significant differences among
species for all three factors (Pvalues for factors
I, II, and III were ,0.0001, ,0.0001, and
0.0002, respectively). No significant difference
was detected among species for Factor IV (P5
0.0796) and it will not be further considered.
For factor I, significant pairwise differences
were detected between C. septentrionalis and
both P. guianensis and C. amazonicus and
between P. guianensis and L. xanthostigma
(Games-Howell post-hoc test, Pvalues ,
0.05). For factor II, all pairwise comparisons
were significant (Games-Howell post-hoc test,
P,0.05). For factor III, C. septentrionalis was
significantly different from both C. amazonicus
and L. xanthostigma (Games-Howell post-hoc
test, P,0.05).
Tail Loss
Tail lengths (original complete tails) were
significantly correlated with lizard SVL in all
FIG. 4.—Evolutionary relationships among Neotropical
leaf litter geckos showing differences in foot structure (toe
drawings from Kluge, 1995 except for those of C.
septentrionalis, which were taken from Avila-Pires,
1995). a 5lateral view, b 5dorsal view, c 5ventral view
of toes.
FIG. 5.—Body size distributions for Neotropical leaf
litter geckos. Lines with closed circles indicate sample
means.
142 HERPETOLOGICAL MONOGRAPHS [No. 19

species (Pvalues ,0.0139; Table 4). An
ANCOVA on tail length with SVL as the
covariate revealed no significant difference
among populations of C. amazonicus (F
1,5
5
1.8, P50.1292, after removing the non-
significant interaction term). Consequently, we
combined all data for C. amazonicus for further
comparisons. An ANCOVA comparing tail
length among species with SVL as the covariate
revealed a significant effect (F
1,2
544.3, P,
0.001 after removing the non-significant in-
teraction term). All species pairs were signif-
icantly different (all Pvalues ,0.0013, Fisher’s
protected least significant difference test
[PLSD]). Tail loss rates varied from 45.5–
81.8% among species and original tails ac-
counted for 43.7–51.3% of total length among
species (Table 5). When tails were lost, on
average, more than half of the tail was missing
or had been missing prior to regeneration. The
greatest portion of the tail lost was in C.
amazonicus, in which an average of only 24.5%
of the original tail remained. The lowest
portion of the tail lost was in C. septentrionalis,
which averaged 49.5% of the original tail
remaining. Nevertheless, considerable varia-
tion exists in position of tail breaks as shown in
Fig. 7. Length of regenerated tails (including
TABLE 2.—Summary statistics for morphological variables on four species of leaf litter geckos. Values shown are means 6
SE, sample size appears after comma and minimum–maximum values are in parentheses under each entry.
Variable C. amazonicus C. septentrionalis L. xanthostigma P. guianensis
Snout–vent length (mm) 20.7 60.2, 220
(11.6–24.6)
27.2 60.5, 44
(18.4–32.0)
32.5 61.5, 11
(19.0–37.0)
24.4 60.8, 23
(14.4–28.5)
Mass (g) 0.21 60.01, 219
(0.04–0.4)
0.45 60.02, 44
(0.15–0.7)
0.71 60.10, 11
(0.10–1.4)
0.29 60.02, 23
(0.08–0.5)
Head width (mm) 3.33 60.02, 207
(2.5–4.1)
4.14 60.05, 44
(3.1–4.5)
4.89 60.11, 10
(4.2–5.4)
3.64 60.07, 23
(2.7–4.0)
Head length (mm) 4.58 60.04, 206
(3.4–7.1)
5.75 60.08, 44
(4.1–6.6)
7.44 60.14, 10
(6.8–8.4)
5.14 60.14, 23
(3.4–6.2)
Head height (mm) 2.22 60.02, 206
(1.5–3.4)
2.62 60.04, 44
(1.9–3.2)
3.29 60.08, 10
(3.0–3.8)
2.44 60.08, 23
(1.2–3.0)
Body width (mm) 3.92 60.04, 207
(2.1–5.2)
5.19 60.13, 44
(3.0–6.9)
5.61 60.12, 10
(4.9–6.1)
4.30 60.16, 23
(2.6–5.6)
Body height (mm) 2.77 60.03, 207
(1.6–3.8)
3.62 60.10, 44
(2.3–5.0)
4.41 60.13, 10
(3.6–5.0)
3.27 60.12, 23
(2.2–4.4)
Hindleg length (mm) 7.25 60.05, 207
(4.6–8.9)
8.63 60.13, 44
(5.9–10.2)
11.44 60.34, 10
(9.3–12.6)
8.19 60.19, 23
(5.7–9.7)
Foreleg length (mm) 5.27 60.06, 133
(3.6–6.9)
6.80 60.14, 44
(4.2–8.8)
8.25 60.23, 10
(6.6–9.1)
5.64 60.19, 23
(3.3–7.1)
FIG. 6.—Plot of first two factors from a Principal
Components Analysis on size-adjusted morphological
variables of four Neotropical leaf litter geckos. Lepido-
blepharus xanthostigma was most different from the other
species. See Table 2 for factor scores.
TABLE 3.—Factor scores from a Principal Components
Analysis on seven size-adjusted morphological variables
for four species of leaf litter geckos.
Variable Factor 1 Factor 2 Factor 3
Relative mass 0.685 0.448 ,0.001
Relative head width 0.621 0.078 0.226
Relative head length 0.621 0.368 0.407
Relative head height 0.521 0.132 0.014
Relative body width 0.021 0.771 0.053
Relative body height 0.001 0.122 0.002
Relative hindleg length 0.015 0.089 0.864
Relative tail length 0.180 0.641 0.370
Eigenvalue 1.851 1.526 1.049
Percent of variation 23.1 19.1 13.1
2005] HERPETOLOGICAL MONOGRAPHS 143

the original; tail base) averaged considerably
less than original tails (64.9–78.8%).
Diets
The number of prey types recorded for each
population/species of geckos was significantly
correlated with sample size (R
2
50.774,
F
1,7
524.3, P50.0017; Fig. 8). However, prey
diversity based on volumetric data was not
correlated with sample size (F
1,7
,0.1, P5
0.9767). Even though additional prey types
were added as sample size increased with
species, prey types comprising most of the diet
volumetrically did not change. Although some
dietary variation existed among populations of
C. amazonicus (Fig. 9), springtails, termites,
homopterans, and insect larvae dominated
their diets at all sites. Coleodactylus septen-
trionalis ate mostly termites and grasshoppers
and crickets. Lepidoblepharis xanthostigma
had a diet volumetrically dominated by verte-
brates. Spiders and springtails accounted for
most of the remainder of their diet. However,
close examination of diet data for that species
revealed that a single lizard had eaten a rela-
tively large frog accounting for all of the ver-
tebrate material. In addition, sample size for
this species was low (N 59). Consequently,
any conclusions are tentative at best. Nev-
ertheless, other leaf litter geckos did not
eat vertebrates (sample sizes/species varied
from 22–196). Pseudogonatodes guianensis ate
mostly insect larvae and small grasshoppers
and crickets.
The null model analysis (Winemiller and
Pianka’s ‘‘pseudocommunity’’ analysis) of di-
etary data provided some insight into prey use
among populations and species. Overlaps in
volumetric data varied from 0.651 between
Rio Ituxi and Rondo
ˆnia 99 C. amazonicus to
0.022 between X. septentrionalis and L.
xanthostigma (Table 6). At the first nearest
neighbor rank, empirically measured dietary
overlaps were not significantly greater than
those generated by either simulation (Fig. 10).
However, at ranks 2–7 type I overlaps were
significantly lower than measured overlaps.
Variability in dietary overlaps (as measured by
SD) was higher for measured overlaps at
ranks 2–7 as well (Fig. 10). Populations of
C. amazonicus were similar in diets across
several ranks (Fig. 11); the first, second, and
in some cases, third nearest neighbors in
dietary niche space were other populations of
C. amazonicus. Ranked dietary overlaps in
diets of C. septentrionalis and P. guianensis
dropped at rank 2 indicating low overlaps with
TABLE 4.—Statistics on the relationship between tail length and SVL and regression equations for four species of leaf litter
geckos. In the equations, estimated tail length 5yand SVL 5x. These equations were used to estimate original tail
lengths for geckos with recently broken or regenerated tails (see text).
Variable C. amazonicus C. septentrionalis L. xanthostigma P. guianensis
R
2
0.544 0.201 0.958 0.780
Ftest F
1,107
5130.1 F
1,22
56.8 F
1,3
570.2 F
1,7
529.3
Pvalue ,0.0001 0.0162 0.0139 0.0010
Equation y50.760(x)þ1.636 y50.382(x)þ10.881 y51.371(x)8.134 y50.665(x)þ4.242
TABLE 5.—Statistics on tail break frequencies, relative tail lengths, and relative position at which tail autotomy occurred
for four species of leaf litter geckos. T
b
5tail base, T
r
5regenerated portion of tail, and tail
est
5estimated original tail
length. Numbers in parentheses are min–max for relative tail length and position and number broken/total number for %
regenerated tails.
Variable C. amazonicus C. septentrionalis L. xanthostigma P. guianensis
% regenerated tails 50.7 (112/221) 45.5 (20/44) 81.8 (9/11) 60.9 (14/23)
Lizards with complete tails
Tail/SVL (%) 84.1 60.7 (109) 77.8 61.2 (24) 106.0 65.8 (4) 85.9 62.6 (9)
Tail/(SVL þTail) (%) 45.6 60.2 (109) 43.7 60.4 (24) 51.3 61.4 (4) 46.1 60.8 (9)
Lizards with lost or regenerated tails
T
b
/tail
est
(%) 24.5 62.4 (112) 49.5 65.6 (19) 36.1 69.3 (10) 44.6 66.1 (14)
(T
b
þT
r
)/tail
est
(%) 70.0 62.2 (112) 69.0 65.6 (19) 64.9 67.6 (10) 78.8 63.8 (14)
144 HERPETOLOGICAL MONOGRAPHS [No. 19

most other species and populations. The diet
of L. xanthostigma remains different from all
others at all but the last rank, most likely
a result of the frog eaten by a single in-
dividual.
Prey size and the number of prey types used
varied among gecko species and populations
(Table 7). Lizard body size (SVL) accounted
for 86.7% of the variation in mean prey size
among species and populations (F
1,7
553.1,
P50.0002; mean prey volume 50.226 [mean
SVL] 4.5; Fig. 12). Larger species and/or
populations of leaf litter geckos ate larger prey
on average. With all species and populations
combined, a significant relationship between
log
10
of mean prey volume per individual
lizard and log
10
SVL exists (R
2
50.286,
F
1,266
5108.2, P,0.0001; Fig. 13). An
ANCOVA on log
10
of mean prey volume per
individual lizard with log
10
SVL as the co-
variate and locality/species as the class variable
revealed no differences in slopes (F
1,8
50.9,
P50.5136) of the regression models for each
species, so we removed the interaction term
and reran the ANCOVA. The ANCOVA
detected significant differences in mean prey
size independent of differences in lizard SVL
(F
1,8
59.7, P,0.0001). Eighteen of 36
pairwise comparisons were significant (P,
0.05, Fisher’s PLSD). Only four of those were
differences between populations of C. ama-
zonicus (Rondo
ˆnia 85 versus Rondo
ˆnia 99, Rio
Ituxi versus Rondo
ˆnia 99, Rio Ituxi versus
Curua
´-Una, and Rondo
ˆnia 85 versus Curua
´-
Una). Remaining differences were between
species, and the magnitudes of the species
differences were greater than those for pop-
ulations of C. amazonicus. Thus, overall
species differences in diets were greater than
population differences within C. amazonicus.
Moreover, C. amazonicus and C. septentrio-
nalis from the same locality had very differ-
ent diets.
DISCUSSION
Leaf litter geckos in this study are closely
related phylogenetically (Kluge, 1995), and,
among South American lizards, are rivaled in
small body size by only a few sphaerodactyline
geckos and a few gymnophthalmids (e.g.,
Leposoma; Vitt and Zani, 1996a, 1998b). They
seem to be most common in relatively un-
disturbed lowland rainforest, but one species,
C. amazonicus, can be found in a variety of
habitats as long as leaf litter exists on the forest
floor and the canopy is dense enough to keep
FIG. 7.—Relative positions of tail breaks for four
Neotropical leaf litter geckos. To aid interpretation,
a drawing above the graph shows a tail that was broken
near the tip with a small regenerated portion. Its tail
base (the original portion) represents 80% of the original
tail length.
FIG. 8.—Relationship between number of prey types for
all species and populations of Neotropical leaf litter geckos
and the number of lizards sampled. Each point represents
a species or population.
2005] HERPETOLOGICAL MONOGRAPHS 145

sunlight from heating up the forest floor. All
are active throughout the day regardless of
whether sun is available. Occasional nocturnal
activity on moonlit nights has been observed in
one species (C. amazonicus; Hoogmoed and
Avila-Pires, 1989). Based on temperatures in
the microhabitats where they are found, they
appear to be active with body temperatures
near 27 C. Leaf litter temperatures in shaded
forest fall within the range of microhabitat
temperatures recorded for captured geckos
whereas leaf litter temperatures in a natural
forest treefall were much higher, suggesting
that treefalls are not suitable. We found only
a few C. amazonicus and none of the other
species in treefalls, suggesting that they avoid
them. The observation that these lizards were
found in leaf litter with slightly higher temper-
atures than hourly means suggests that the
geckos are not randomly distributed on the leaf
litter, but may select microsites with temper-
atures slightly higher than average. Most likely,
opening the canopy would have negative
impact on populations of these tiny geckos
because the ground surface would heat up
producing a thermally extreme microhabitat,
even if leaf litter is present, as is the case for
natural treefalls (see Vitt et al., 1998a).
The most striking aspect of the morphology
of these leaf litter geckos is their small size. In
Amazonian rainforest, Coleodactylus,Lepido-
blepharus (e.g., L. heyerorum), and Pseudogo-
natodes are the smallest species within their
respective lizard assemblages (see also Avila-
Pires, 1995). For example, among eight
Amazonian localities (not all included in our
analyses), Coleodactylus,Pseudogonatodes,or
Lepidoblepharis are the smallest species, and,
with two exceptions, the next largest species
are gymnophthalmids (Prionodactylus argulus
at three sites, P. eigenmanni at one, Leposoma
parietale at one, and L. percarinatum at one).
At the Rio Xingu in Para
´,C. amazonicus is the
FIG. 9.—Summary of volumetric data on prey types
eaten by Neotropical leaf litter geckos. Data are presented
as proportional utilization coefficients (p
i
) to facilitate com-
parisons among species and with other published data.
Although some prey categories appear to have zero en-
tries across species, trace amounts were present (see
Appendix A).
146 HERPETOLOGICAL MONOGRAPHS [No. 19

smallest and L. heyerorum is the second
smallest. In Amazonian Roraima, C. amazoni-
cus is the smallest and C. septentrionalis is the
second smallest. Only at the Rio San Juan in
Nicaragua is there a smaller species. There,
a gecko in the same clade, Sphaerodactylus
millipunctatus, is smaller than L. xanthostigma
(see Vitt and Zani, 1998a). We suggest that
small body size has allowed these geckos to
survive as leaf litter inhabitants in a variety of
diverse lizard assemblages in tropical Central
and South America. Small body size likely
provides access to the highly complex struc-
ture of leaf litter on the forest floor, thus
facilitating escape from some predators. In
addition, small body size allows these lizards to
take advantage of tiny prey items apparently
abundant in leaf litter but not eaten by most
larger lizards. These geckos eat some of the
smallest invertebrates in the leaf litter (e.g.,
collembolans, tiny insect larvae, early instars of
homopterans; see below). Even lizards in the
sister taxon, Gonatodes, not only eat larger
prey items than any of the leaf litter geckos,
but prey that differ taxonomically (e.g., Vitt
et al., 1997b, 2000).
Significant differences in bauplan are evi-
dent as well. All three genera have toe tips that
lack the prominent exposed claws found in the
sister taxon Gonatodes (Fig. 4). Rather, claws
are reduced and hidden within a sheath of
scales. The shape of the ungual sheath also
differs among the three genera. In Coleodac-
tylus, one scale makes nearly complete contact
with the substrate. In Lepidoblepharus and
Pseudogonatodes, the sheath is bilaterally
TABLE 6.—Empirically generated dietary overlaps among populations of C. amazonicus and species of leaf litter
geckos. g
i
data were used to calculate overlaps (see Methods). Where locality only is indicated, the species is
Coleodactylus amazonicus.
Species/population Amazonas Curua Una Rio Ituxi Rond. 85 Rond. 99 Roraima C. sep.L. xanth.P. guian.
Amazonas 1.000
Curua
´-Una 0.645 1.000
Rio Ituxi 0.641 0.383 1.000
Rondo
ˆnia 85 0.382 0.455 0.264 1.000
Rondo
ˆnia 99 0.627 0.584 0.651 0.498 1.000
Roraima 0.461 0.400 0.194 0.427 0.332 1.000
C. septentrionalis 0.552 0.256 0.140 0.133 0.208 0.303 1.000
L. xanthostigma 0.118 0.061 0.117 0.156 0.082 0.050 0.022 1.000
P. guianensis 0.422 0.379 0.254 0.253 0.644 0.297 0.339 0.066 1.000
FIG. 10.—Pseudocommunity analysis on volumetric
prey data (see Methods).
FIG. 11.—Plots by species of ranked overlaps versus the
rank of each species’ nearest neighbor in dietary niche
space.
2005] HERPETOLOGICAL MONOGRAPHS 147

symmetrical and laterally compressed such
that no scale makes broad contact with the
substrate. Although the function of these
complicated ungular sheaths remains unclear,
they may aid in moving across surfaces of
leaves that do not provide firm support for the
gecko’s body. It is possible, for example, that
claws would interfere with the gecko’s ability
to jump from leaf to leaf. Lepidoblepharis
xanthostigma has a relatively larger head and
relatively more streamlined torso than the
other genera studied here. Pseudogonatodes
has the smallest relative head size and is
intermediate between Lepidoblepharis and
Coleodactylus in relative body shape. Both
species of Coleodactylus are the most robust
in body shape. At this point, we can only
speculate on reasons that underlie these
differences. Coleodactylus frequently jump
from leaf to leaf, and their short, robust body,
coupled with their slightly expanded club-like
toe tips may facilitate such behavior. We have
observed Lepidoblepharis ‘‘swimming’’ on the
surface film of water where they use lateral
undulation to propel themselves forward.
Their relatively elongate body may facilitate
this type of locomotion. Evolutionarily, a re-
duction in relative head size has occurred in
the more derived species and may facilitate
capture of small prey.
We interpret the pseudocommunity analysis
of leaf litter gecko diets as follows. First,
similarity of measured overlaps at the nearest
neighbor rank 1 results from the great degree
of similarity in diets among populations of C.
amazonicus. Common use of a few prey types
accounted for most of this similarity. More-
over, this result supports our premise that
similarities and differences observed reflect
biological differences among the species,
TABLE 7.—Summary statistics for prey sizes for from six populations of Coleodactylus amazonicas and three other leaf
litter gecko species. Linear measurements are in mm and volumetric measurements are in mm
3
. No. types is the number
of prey categories (see Methods). Minimum and maximum values appear in parentheses.
Variable
Coleodactylus amazonicus Other leaf litter geckos
Solim~
oes Curua
´-Una Rio Ituxi Rondo
ˆnia 85 Rondo
ˆnia 99 Roraima C. septent.L. xantho.P. guianensis
No. lizards 35 35 20 68 16 22 43 9 22
No. types 19 18 15 22 14 12 18 7 12
No. prey 467 370 161 604 258 240 318 23 164
Prey length 1.14 60.04
(0.27–6.23)
1.22 60.04
(0.21–6.15)
1.58 60.07
(0.17–5.08)
1.23 60.03
(0.20–7.18)
1.15 60.06
(0.27–6.44)
1.33 60.06
(0.45–9.49)
2.08 60.1
(0.31–10.89)
2.52 60.34
(1.35–8.91)
1.54 60.09
(0.20–8.30)
Prey width 0.36 60.01
(0.12–2.00)
0.35 60.01
(0.07–2.14)
0.47 60.02
(0.10–1.51)
0.45 60.02
(0.10–6.43)
0.35 60.01
(0.12–1.54)
0.44 60.02
(0.17–3.80)
0.81 60.03
(0.15–3.59)
0.93 60.12
(0.39–3.02)
0.43 60.02
(0.10–1.50)
Prey volume 0.23 60.04
(0.01–10.81)
0.16 60.03
(0.01–8.08)
0.33 60.05
(0.01–3.57)
0.31 60.07
(0.01–28.79)
0.13 60.02
(0.01–3.64)
0.25 60.05
(0.01–7.86)
2.23 60.38
(0.01–62.09)
2.79 61.82
(0.11–42.55)
0.28 60.04
(0.01–4.12)
FIG. 12.—Plot of mean prey volumes (species and
populations) for Neotropical leaf litter geckos against mean
body size (SVL). Each point represents a mean for
a species or population.
FIG. 13.—Mean prey volumes for individual lizards
plotted against their SVL. Variables were log-transformed
to approximate normal distributions.
148 HERPETOLOGICAL MONOGRAPHS [No. 19

rather than geographical variation in resource
use, especially considering that the forests are
structurally different and at least some varia-
tion in diets is likely associated with variation
in seasons and localities in which we sampled.
At lower ranks, measured overlaps were
more similar than expected by chance for the
type I simulation indicating that even though
diets differed among species, a few prey types
dominated the diets of all species and pop-
ulations, but rarer prey types were generally
not shared. Although our understanding is
limited by small sample size, L. xanthostigma,
appeared to be a specialist compared with the
others (Fig. 8). This may not be an accurate
representation because of the disproportionate
effect a single, relatively large frog in the diet
of one lizard had on the diet summary for the
species. Overall, we conclude that these tiny
lizards feed on a variety of small prey but, with
the exception of P. guianensis, seem to prefer
collembolans, insect larvae, homopterans, and
spiders. Surprisingly few ants were recorded in
most leaf litter gecko stomachs even though
these are common prey of some dendrobatid
frogs in the same leaf litter (e.g., Caldwell and
Vitt, 1999; Vitt and Caldwell, 1994). Most ants
eaten by dendrobatid frogs, and presumably
many ants that occur in leaf litter are
myrmicine ants capable of producing noxious
chemicals. These leaf litter geckos may detect
and avoid ants and other noxious insects using
their nasal chemosensory system (Cooper,
1995, 1997; Pianka and Vitt, 2003; Schwenk,
1995). The chemosensory system of sclero-
glossan lizards is much better developed than
that in iguanian lizards, the latter of which are
known to eat considerable numbers of ants
(e.g., Pianka and Vitt, 2003; Vitt et al., 2003a).
Some species even specialize on them (e.g.,
Phrynosoma; Pianka and Parker, 1975) in-
dicating that ants are not necessarily bad prey
items under the right circumstances.
Even though these lizards appear to eat
a wide variety of small prey, it appears unlikely
that differences in prey availability alone
account for differences among species. In
Roraima, C. amazonicus and C. septentrionalis
occur together in leaf litter, yet their diets are
very different (see also Ramos, 1979). Coleo-
dactylus septentrionalis in Roraima fed mostly
on termites whereas C. amazonicus in Roraima
ate mostly springtails and small flies. Flies
were rare in diets of other populations of
C. amazonicus and thus the difference in diet
of the Roraima C. amazonicus population may
reflect the effects of interactions with C.
septentrionalis at that site. These data add
support to the notion that lizards, especially
scleroglossans, are selective in their use of prey
and do not simply take a random sample of
what is available (see also Pianka, 1986; Vitt
and Pianka, 2004).
The observation that larger individuals and
species of leaf litter geckos eat larger prey
is consistent with studies on other lizards, par-
ticularly scleroglossans (e.g., Vitt and Pianka,
2004). Primary exceptions to this postulate
are lizard species that specialize on termites
or ants such as iguanian lizards in the genera
Plica and Uracentron (e.g., Vitt, 1991; Vitt
and Zani, 1996b; Vitt et al., 1997c).
Prey items eaten by other species of lizards
at all sites are considerably different from prey
items eaten by these leaf litter geckos (e.g., Vitt
and Zani, 1996a, 1998a,b). Indeed, prey items
eaten by most other lizards are at least an order
of magnitude larger than those eaten by these
leaf litter geckos. In addition to potential
predator escape advantages discussed above,
small body size of these leaf litter geckos may
have allowed them to take advantage of prey
resources effectively unavailable to most other
lizards. If small body size does account for
their ability to use tiny prey, small body size in
the clade could be a key innovation allowing
exploitation of food resources not used by
ancestral lineages. The kinds of prey eaten by
these lizards may also be restricted to leaf litter
microhabitats for the same reason as these
lizards. Small body size (in geckos and
invertebrates) may put them at risk of hypo-
thermy and desiccation in more open habitats.
Considering the large number of tiny lizards
(gekkonids and gymnophthalmids) and frogs
(dendrobatids, microhylids, bufonids, and
leptodactylids) that inhabit leaf litter in New
World tropical forests, it is surprising how few
detailed studies exist on their ecology (but see
Caldwell and Vitt, 1999; Lieberman, 1986; Vitt
and Caldwell, 1994). A recent book focusing
on tiny vertebrates (Miller, 1996) identifies
lizards as containing among the smallest
sauropods that have ever lived. Among lizards,
less than 5% of those included in a survey of
lizards (Avery, 1996) were less than 30 mm
2005] HERPETOLOGICAL MONOGRAPHS 149

SVL. However, Avery’s estimates are biased
because he did not include Central America or
any of tropical South America, both of which
have many tiny gekkonids and gymnophthal-
mids. Most of Avery’s discussion on the
ecology of small size centers on Anolis and
Cnemidophorus, both of which average more
than an order of magnitude larger in mass than
the geckos studied here. Moreover, most
Anolis and Cnemidophorus, even when they
hatch from eggs, are large enough to not be
prey of most invertebrates (although tropical
spiders, centipedes, and amblypygids can
capture some fairly large lizards). Some of
the most interesting aspects of the ecology of
lizards the size of these geckos will be their
potential interactions with invertebrates, both
as prey and as competitors. High rates of tail
loss that we have reported here suggest that
predation attempts are common, and to date
we have no information on predator success.
However, the possibility exists that some tail
loss in males results from social interactions
(see Vitt et al., 1974), which would be detect-
able based on sexual differences in tail loss
frequency. Tail loss rates for C. amazonicus,
the species for which we have sufficient data,
are slightly higher for females (52.6%, 51/97)
than males (46.8%, 58/124), the opposite of
predictions based on the hypothesis that male–
male interactions result in tail loss.
Finally, it seems apparent, that like many
other rainforest amphibians and reptiles that
depend on relatively low temperatures, shade,
and leaf litter, alteration of tropical rainforest
will undoubtedly have dire consequences for
these tiny lizards (e.g., Vitt and Zani, 1996c;
Vitt et al., 1998a,b, 2002, 2003b). In addition to
reducing inhabitable microhabitats, opening
the forest provides access to large, highly
active, heliothermic lizards that can prey on
small vertebrates (Sartorius et al., 1999; Vitt
et al., 1998a).
Acknowledgments.—We first thank the various people who
contributed to this work by helping collect specimens;
C. Morato de Carvalho, J.M. Howland, P.T. Lopez, G.R.
Colli, V. Oliveira, A. C. Marinho Lima, A. A. Monteiro de
Barros, A. Lima, R. Souza, and especially M. C. Arau
´jo.
Brazilians and Brazilian companies too numerous to name
helped significantly with logistics, but we especially thank
W. E. Magnusson and the Instituto Nacional de Pesquisas
da Amazo
ˆnia (INPA). We thank M.S. Hoogmoed for
commenting on the manuscript. Permits to conduct
research and collect specimens in Brazil were issued by
Conselho Nacional de Desenvolvimento Cientı
´fico e
Tecnolo
´gico (CNPq, Portaria MCT no. 170, de 28/09/94)
and the Instituto Brasileiro do Meio Ambiente e dos
Recursos Naturais Renova
´veis (IBAMA. no. 073/94-
DIFAS), respectively under a research convenio between
the Oklahoma Museum of Natural History and the Museu
Paraense E. Goeldi. Milton Camacho of the Departamento
de Fauna Silvestre facilitated collecting and export permits
for Nicaragua. Portions of this research were supported by
two National Science Foundation grants (DEB-9200779
and DEB-9505518) to LJV and J. P. Caldwell. Early work
in Brazil was supported entirely by the Brazilian govern-
ment, primarily through grants to P.E. Vanzolini at the
MZUSP.
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APPENDIX A
Raw volumetric dietary data for leaf litter geckos. For C. amazonicus populations, SO 5Solim~oes, CU 5Curua-Una,
RI 5Rio Ituxi, RO85 5Rondo
ˆnia 1985, RO98 5Rondo
ˆnia 1999, and RR 5Roraima.
Prey category
Coleodactylus amazonicus
C.
septentrionalis L.
xanthostigma P.
guianensis Totals
SO CU RI RO 85 RO 99 RR
Grasshoppers
& Crickets 5.89 0 1.89 3.29 2.09 0 165.55 0 10.42 189.13
Ants 2.31 1.55 0 0.46 0 1.92 0.08 0 0 6.32
Beetles 3 8.45 0.03 1.61 0.38 0.03 0 0 0 13.5
Centipedes 0 0 0 0.55 0 0 0.12 0 0 0.67
Earthworms 0 0.09 0 0 0 0 0.82 0 0 0.91
Embiopterans 0 0 0 0.01 0 0 0 0 0 0.01
Flies 4.29 0.23 0.51 1.92 0.3 15.95 9.73 0 1.77 34.7
Hemipterans 1.54 0.95 0 2.11 0.39 1.32 0.8 0 0.5 7.61
Homopterans 21.5 5.61 23.65 5.11 6.72 0.23 5.08 3.78 1.55 73.23
Insect larvae 8.75 12.06 3.67 18.48 9.34 8.69 39.74 2.42 18.49 121.64
Isopods 3.02 2.14 5.81 0 0 2.41 13.56 0 0 26.94
Lepidopterans 0 0 0 6.72 0 0 0 0.94 0 7.66
Lizard shed skin 0 0 0 0 0 0 44.67 0 0 44.67
Millipedes 11.95 3.25 1.73 5.81 3.69 0 14.16 0 3.27 43.86
Mites 0.95 1.52 3.25 10.02 1.75 0.08 1.3 0 0.02 18.89
Non-ant
hymenopterans 0.49 0.24 0 0.76 0 0 0 0 0 1.49
Opiliones 0.61 0.77 0.58 0.08 0.64 0 2.99 0 4.1 9.77
Pseudoscorpions 0.53 0.2 1.26 0.87 1.2 0 5.74 0 0 9.8
Psocopterans 0.36 0.07 0.81 0 0.66 0 0 0 0 1.9
Roaches 1.82 0 0 16.18 0 0 0 1.88 0 19.88
Snails 0 0 0.12 0 0.39 1.22 21.58 0 0.03 23.34
Spiders 7.48 0.73 4.58 9.73 0.4 1.2 19.71 7.8 2.28 53.91
Springtails 9.66 13.31 5.01 99.37 6.88 18.66 36.74 4.69 3.25 197.57
Termites 21.47 6.24 0.66 4.42 0 8.14 326.19 0 0 367.12
Thysanopterans 0.47 0.32 0 0 0 0 0 0 0.06 0.85
Ticks 0 0 0 0.06 0 0 0 0 0 0.06
Vertebrates 0 0 0 0 0 0 0 42.55 0 42.55
Walking sticks 0 0 0 0.05 0 0 0 0 0 0.05
Totals 106.09 57.73 53.56 187.61 34.83 59.85 708.56 64.06 45.74 1318.03
152 HERPETOLOGICAL MONOGRAPHS [No. 19