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Diet composition of Ameerega picta (Tschudi, 1838) from the Serra da Bodoquena region in central Brazil, with a summary of dietary studies on species of the genus Ameerega (Anura: Dendrobatidae)

Received: 12.12.2018 Corresponding editor: W. Böhme
Accepted: 03.06.2019 Published: 13.06.2019
Bonn zoological Bulletin 68 (1): 93–96 ISSN 2190–7307
2019 · Landgref Filho P. et al.
The Neotropical genus Ameerega Bauer, 1986 (Anu-
ra: Dendrobatidae), currently includes 31 species of
frogs distributed in Bolivia, Brazil, Colombia, Ecuador,
French Guiana, Guyana, Peru, Surinam, and Venezue-
la (Frost 2019). The spot-legged poison frog Ameerega
picta (Tschudi, 1838) is a small (SVL in males: 24 mm;
females: 26 mm), terrestrial, diurnal frog distributed in
Bolivia (Departamentos Santa Cruz, Cochabamba, Beni,
and La Paz), Brazil (states of Mato Grosso and Mato
Grosso do Sul), Peru (Departamentos Ucayali and Madre
de Dios), Colombia (Departamentos de Amazonas, Meta,
and Putumayo), and Venezuela (state of Bolívar) at al-
titudes of 200 to 2500 m asl (Duellman 2005; Acosta
Galvis 2017; Frost 2019). Ameerega picta is character-
ized as myrmecophagous (Mebs et al. 2010), but studies
on diet composition in different populations are scarce.
Toft (1980) investigated the diet of A. picta (as Dendro-
bates pictus) and 12 syntopic species in Amazonian Peru.
Ramon et al. (2010) determined the diet composition of
A. picta in an area of the Cerrado (Brazilian savanna) in
the municipality of Nova Xavantina in Mato Grosso state
in central Brazil. Considering the previous information
on the diet composition of A. picta throughout its geo-
graphic distribution, new studies could contribute to the
understanding of its trophic ecology. Here, we provide
data on the diet composition of A. picta from the region
of Serra da Bodoquena in the state of Mato Grosso do
Sul, central Brazil. We also provide a summary of dietary
studies on species of the genus Ameerega.
This study was conducted on the Rancho Branco
farm (20º41’S, 56º47’W) located in the municipality of
Bodoquena, state of Mato Grosso do Sul, central Brazil
days) between May and October 2001. Specimens of
A. picta were sampled during the day on the leaf litter
near the margins of the Salobrinha stream using visual
and auditory search methods (Scott & Woodward 1994).
We determined the sex of the specimens collected and
measured snout-vent length (SVL) to the nearest 0.01 mm
using calipers. The specimens collected were euthanized
in 70% ethanol. Voucher specimens were deposited at
Abstract. We provide data on the diet composition of Ameerega picta from the region of Serra da Bodoquena in the state
of Mato Grosso do Sul, central Brazil. We also provide a summary of dietary studies on species of the genus Ameerega.
Key words. Cerrado, dendrobatid frog, feeding habits, trophic ecology.
Scientific note
Diet composition of Ameerega picta (Tschudi, 1838) from
the Serra da Bodoquena region in central Brazil, with a summary of dietary
studies on species of the genus Ameerega (Anura: Dendrobatidae)
Paulo Landgref Filho1, Fabrício H. Oda2, *, Fabio T. Mise3,
Domingos de J. Rodrigues4 & Masao Uetanabaro5
Universidade Federal de Mato Grosso do Sul, Campus Aquidauana, 79200-000, Aquidauana, Mato Grosso do Sul, Brazil
Departamento de Química Biológica, Programa de Pós-graduação em Bioprospecção Molecular, Universidade Regional do
Cariri, 63105-00, Crato, Ceará, Brazil
Departamento de Biologia, Universidade Estadual do Centro-Oeste, 85040-080, Guarapuava, Paraná, Brazil
Instituto de Ciências Naturais, Humanas e Sociais, Universidade Federal de Mato Grosso – Campus Universitário de Sinop,
78557-267, Sinop, Mato Grosso, Brazil
Instituto Nacional de Ciência e Tecnologia de Estudos Integrados da Biodiversidade Amazônica – Núcleo Regional de Sinop,
Sinop, Mato Grosso, Brazil
Rua Clóvis n. 24, 79022-071, Campo Grande, Mato Grosso do Sul, Brazil
* Corresponding author: Email:
Bonn zoological Bulletin 68 (1): 93–96 ©ZFMK
Paulo Landgref Filho et al.94
the zoological collection of the Universidade Federal de
Mato Grosso do Sul (ZUFMS – AMP, Brazil).
In the laboratory, a longitudinal incision was made in
each individual to remove the stomach and determine
the contents under a stereomicroscope. Food items were
used the Student’s t-test (t) to determine differences in
numeric percentage (N%) per prey category between
sexes were found (t = 0.72, p > 0.05), we calculated the
numeric percentage per prey category for the pooled
Fig. 1. Map of the study site in the region of Serra da Bodoquena, municipality of Bodoquena, state of Mato Grosso do Sul, central
Brazil. Brazilian state abbreviations: GO, Goiás; MG, Minas Gerais; MS, Mato Grosso do Sul; MT, Mato Grosso; PR, Paraná; SP,
São Paulo.
Fig. 2. Specimen of Ameerega picta from region of Serra da
Bodoquena, municipality of Bodoquena, state of Mato Grosso
do Sul, central Brazil.
Table 1. Relative number (N%) of prey categories consumed
by Ameerega picta (N = 50) in the region of Serra da Bodoque-
na in the municipality of Bodoquena, state of Mato Grosso do
Sul, central Brazil (percentages shown in parentheses).
Prey categories N (%)
Formicidae 40 (22.6)
Coleoptera (both larvae and adults) 39 (22.0)
Diptera 29 (16.4)
Homoptera 17 (9.6)
Araneae 22 (12.4)
Arthropod remains 30 (16.9)
Total 177 (100)
Diet composition of Ameerega picta from the Serra da Bodoquena region
Bonn zoological Bulletin 68 (1): 93–96 ©ZFMK
We examined 61 specimens of Ameerega picta (Fig. 2),
50of which(82%)hadstomachcontents.Weidentied
177preyitemsinvepreycategories belonging to the
classes Insecta and Arachnida. The most numerous prey
items in the diet composition of A. picta were Formicidae
(23%), Coleoptera (22%) and Diptera (16%) (Tab. 1). A
small variety of prey and high abundance of Formicidae
have been found in the diet of other populations of A. pic-
ta (Toft 1980; Ramon et al. 2010) and congeneric species,
such as A. bilinguis, A. braccata, A.avopicta, A. hahne-
li, A. parvula, A. petersi and A. trivitatta (Toft 1980;
Biavati et al. 2004; Darst et al. 2005; Forti et al. 2011;
Luiz et al. 2015). The sequester of chemical defenses
from dietary sources is an important adaptation to the an-
ti-predator defense of dendrobatid frogs, as their diurnal
habits result in greater exposure to predators (e.g., Luiz
et al. 2015). The diet composition pattern of these species
of Ameerega is related to their dietary specialization on
ants, which are the source of the toxic alkaloids secreted
through the skin (Saporito et al. 2004; Darst et al. 2005;
Mebs et al. 2010). Some dendrobatid species that feeds
on ants and/or mites in higher proportions have been con-
sidered “ant-mite specialists” (Simon & Toft 1991; Toft
1995; Caldwell 1996). However, mites have been sug-
gested to be more important than ants as dietary sourc-
es of alkaloids in poison frogs (Saporito et al. 2007). In
the present study, we found high abundance of Formici-
dae, Coleoptera and Diptera and absence of mites in the
diet composition of A. picta from region of the Serra da
ation of these prey items in the habitats from which the
frogs were sampled.
Although Ameerega picta exhibits sexual dimorphism
in body size (Uetanabaro et al. 2008), we did not nd
any signicant difference between sexes regarding nu-
meric percentages per prey category. Differences in diet
composition between males and females are reported for
A. braccata and A. trivitatta (Forti et al. 2011; Luiz et al.
2015), which may be related to behavioral differences
that enable the partitioning of feeding resources between
We found only seven studies on the diet composition of
eight species of Ameerega (Tab. 2). The eight species of
Ameerega in the dietary studies analyzed correspond to
26% of the species in this genus, demonstrating that the
diet of most species of the genus is unknown. Therefore,
further studies should focus on species of Ameerega and
another dendrobatid species with undetermined diet in
order to improve the understanding of the trophic ecolo-
gy of the poison frogs.
Acknowledgments. The authors would like to thank the
Fundação Grupo Boticário de Proteção à Natureza (process
#046820002) and project Padrões de biodiversidade da fauna
A. bilinguis Parque Nacional Yasuní, Francisco de Orellana province (ECU)
Estación Biológica Jatun Sacha, Napo province (ECU)
Darst et al. (2005)
A. braccata Chapada dos Guimarães, MT (BRA) Forti et al. (2011)
Cuiabá, MT (BRA)
A.avopicta Minaçu, GO (BRA) Biavati et al. (2004)
Alto Paraíso, GO (BRA)
Pirenópolis, GO (BRA)
Caldas Novas, GO (BRA)
Ecological Station of Piratininga, MG (BRA) Lima & Eterovick (2013)
A. hahneli Parque Nacional Yasuní, Francisco de Orellana province (ECU)
Estación Biológica Jatun Sacha, Napo province (ECU)
Darst et al. (2005)
A. parvula Estación Biológica Jatun Sacha, Napo province (ECU) Darst et al. (2005)
A. petersi Biological Station Panguana, Huànuco province (PER) Toft (1980)
A. picta Biological Station Panguana, Huànuco province (PER) Toft (1980)
Remanso farm, Nova Xavantina, MT (BRA) Ramon et al. (2010)
Rancho Branco farm, Bodoquena, MS (BRA) This study
A. trivittata Biological Station Panguana, Huànuco province (PER) Toft (1980)
Juruti, PA (BRA) Luiz et al. (2015)
a BRA, Brazil: PA, Pará; MT, Mato Grosso; MS, Mato Grosso do Sul; GO, Goiás; MG, Minas Gerais; ECU, Ecuador; PER, Peru.
Table 2. List of dietary studies on species of Ameerega in South America
Bonn zoological Bulletin 68 (1): 93–96 ©ZFMK
Paulo Landgref Filho et al.96
eoradoPantanal(process #521746/97-3)forhavingprovid-
ed both nancial and logistical support during the eldwork.
nológico for having granted master’s scholarships to Domingos
J. Rodrigues (2000–2001) and Valdir who granted us access to
Assentamento Canaã and provided logistical support. We would
also like to thank Fabrício R.D. Fonseca, Rafael S. Arruda, Re-
nata S. Leão and Tatiana S.F. de Souza for their assistance in
the eld. Fabrício H. Oda receives a postdoctoral fellowship
from the Coordenação de Aperfeiçoamento de Pessoal de Nível
Superior/Fundação Cearense de Apoio ao Desenvolvimento
AcostaGalvisAR (2017) Lista delosAnbios de Colombia.
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... Conversely, Lima and Eterovick (2013) found that small temporal differences on habitat use affected the species diet: at the shores of a reservoir during the dry season it was composed mainly of Acari, Lepidoptera larvae and spiders (in number) and by Acari, spiders, Lepidoptera larvae and Coleoptera (in volume), while inside a close trench filled with water during the rainy season, frogs ingested mainly Lepidoptera larvae and termites (for number and volume), and ants were not a relevant prey item. The diet of A. picta in Serra da Bodoquena National Park was composed of only five categories, being dominated by ants, beetles, and Diptera (Landgref-Filho et al. 2019). Ameerega berohoka ingested a larger number of small items as Diptera, Collembola, and Acari, while Coleoptera, Diptera, termites, and ants were the most voluminous ingested items, but preferring collembolans, tricopterans, Acari, and Diptera. ...
... Ameerega berohoka ingested a larger number of small items as Diptera, Collembola, and Acari, while Coleoptera, Diptera, termites, and ants were the most voluminous ingested items, but preferring collembolans, tricopterans, Acari, and Diptera. Formicidae are relevant prey items for different Ameerega species (Landgref-Filho et al. 2019), and the ingestion of ants can be related to sequestration of alkaloids (Mebs et al. 2010), but ants were ingested by A. berohoka in a smaller proportion than found in the environment, while A. flavopicta prefered lepidoptera larvae in the study of Lima and Eterovick (2013). ...
... However, the consumption of these preys depends on their density and distribution in the environment, and differences in ingestion rates can occur throughout the year (Saporito et al. 2007b;Bull & Hayes 2009;Moskowitz et al. 2018). Although Ameerega flavopicta ingested fewer ants than related species occurring in the Amazon (Biavati et al. 2004;Lima & Eterovick 2013), ants were relevant in the diet of other related species in the Cerrado biome (Forti et al. 2011;Landgref-Filho et al. 2019;present study). Interestingly, social insects, in general, are relevant prey even for Ameerega species occurring in the Amazon (Luiz et al. 2015), and diverse strategies of alkaloid capturing and evolution of skin toxicity are expected to occur within different lineages in the Neotropics (see Darst et al. 2005), including circumstantial sequestration from termites or other arthropods. ...
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Amphibians often use ephemeral and simplified habitats during dry seasons in tropical biomes. These simplified habitats can have less prey available, but only a few studies focus on how their use affects frogs’ diet. Here we studied the diet of three terrestrial frogs (Adenomera sp., Ameerega berohoka, and Rhinella ocellata) at a riverbank exposed only during the dry season in the Brazilian Cerrado biome. Diets overlapped more than expected by chance and were composed mainly of social insects (ants and termites). Prey volumes were not related to the size of frogs or their head measurements. Frogs at the riverbank ingested less prey categories and fewer prey items in comparison to studies conducted in more stable and complex environments. We suggest that frogs were attracted to riverbanks by the humidity and availability of reproductive sites, opportunistically ingesting prey available in the habitat. The abundance of social insects allowed the presence of frogs specialized in ants, such as the bufonid Rhinella ocellata and the dendrobatid Ameerega berohoka.
... Our results showed ants as the most frequent prey category, with the greatest total volume of stomach content and the highest index of relative importance, ingested by A. berohoka and A. picta in the plateaus surrounding the Pantanal of Mato Grosso do Sul. Similar results have been documented for Ameerega picta (Ramon et al. 2010;Landgref-Filho et al. 2019) and other populations of Ameerega from different biomes (Caldwell 1996;Forti et al. 2011;Lima & Eterovick 2013;Luiz et al. 2015). ...
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Santana (2020): Diet and morphometry of two poison frog species (Anura, Dendrobatidae) from the plateaus surrounding the Pantanal of Mato Grosso do Sul state, Brazil, Studies on Neotropical Fauna and Environment, ABSTRACT The plateaus surrounding the Pantanal in Mato Grosso do Sul are highly threatened by land-use conversion and are home to Ameerega berohoka and Ameerega picta, two species of poison frogs renowned for their aposematic coloration and toxic skin. The species have diurnal and terrestrial habitats and are often observed among dead tree branches, leaf litter or under rocks. Herein, we investigated the diet and sexual dimorphism of body size in A. berohoka and A. picta, aiming to increase our understanding of the natural history of both species. We collected A. berohoka specimens from the Bonito municipality and A. picta from the Rio Negro Municipality and obtained 1,600 prey items organized into 12 categories. We found that formicid insects had the highest index of relative importance and were the most frequent prey category for both species. Despite prey items such as Acari and Isoptera being present in the diet of these species, the niche breadth of these species was low. We found no evidence of sexual dimorphism in body size or body shape for A. berohoka and A. picta. Based on our findings, we conclude that both species are ant specialists, as proposed for other Ameerega species. ARTICLE HISTORY
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Diet and transportation of tadpoles by Ameerega trivittata was studied in the eastern Amazon basin. A total of 56 specimens (48 males and 8 females) were sampled, 44 out of which had quantifiable stomach contents. Forty males were recorded to carry between 1 and 18 tadpoles. Forty pools were measured and sampled for tadpoles and odonate naiads, a putative tadpole predator. Myrmicine ants predominated in the diet of males, putatively leading to higher concentrations of alkaloids beneficial during tadpole transport. No relationship was found between male size and the number or size of tadpoles transported, and between pool size and tadpole abundance. The number of tadpoles in the pools was negatively related to the abundance of odonate naiads.
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We studied a population of Ameerega flavopicta on an island in southeastern Brazil that was formed during the filling of a reservoir in 1965. We studied frog condition factor, diet composition (through induced regurgitation), prey preferences (based on prey availability assessed at frogs' habitats), vocalizations, breeding period, and density. We conducted fieldwork monthly from July 2008 to March 2010 to locate frogs in marked grids. We photographed individual frogs to register particular patterns of dots on the dorsum that allowed individual recognition. During the rainy season A. flavopicta used a temporary trench inside the inland vegetation (Cerradão) for tadpole development. The frogs migrated to the margins of the reservoir during the dry season, when the trench dried completely. Frogs measured 24.0 ± 4.0 mm (snout–vent length), and mass was 1.6 ± 0.5 g (N = 47). Their condition varied among months but not between the two areas used (trench surroundings inland and island shores). Ameerega flavopicta favored specific food items and preferred Lepidoptera larvae in both areas. The advertisement call was composed of simple notes repeated 102.7 ± 7.63 times per min, lasting 166 ± 42 msec and spaced by 387 ± 66 msec. The breeding period differed from that reported for other areas. This and other aspects of the Pirapitinga population differed from populations studied elsewhere. Differences may be attributable to a bottleneck effect or different selective pressures in this isolated population.
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Frogs of the family Dendrobatidae and Microhylidae are myrmecophagous, i.e., they feed on ants. It is well accept-ed that toxic alkaloids in the skin secretion of dendrobatid frogs are of dietary origin and may derive from ants. Alcohol ex-tracts from specimens of Ameerega picta (Dendrobatidae) and of Elachistocleis sp. (Microhylidae) from two locations in Bo-livia were analyzed by gas chromatography-mass spectrometry. Whereas the extracts of Ameerega picta specimens exhibited a typical profile of toxic alkaloids, those from Elachistocleis sp. were alkaloid-free. Fecal samples from both frogs consisted of ant remnants. These results indicate that myrmecophagy provides dendrobatids with alkaloids, which they sequester and store in their skin, but an alkaloid sequestering system is absent in the microhylid Elachistocleis sp.
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A central issue in comparative biology is identifying the relative importance of historical (phylogenetic) versus present-day (ecological) factors in shaping phenotypic traits of organisms. Herein, we investigate effects of sex, ontogeny, and season on diet of Epipedobates flavopictus, a species restricted to open landscapes in central Brazil. Based on prey frequency, number, and volume, the most important prey categories were ants, termites, beetles, spiders, and orthopterans. Prey number and volume increased significantly with snout–vent length (SVL), and the consumption of termites also increased with SVL. There were few effects of sex and season upon diet composition, average prey number, or average prey volume, all independent of SVL. Reproductive females consumed larger prey, in great numbers, likely to increase energy uptake. As is true for most congeners, as well as species of closely related genera, ants are an important component in the diet of E. flavopictus. However, in contrast to its forest relatives, E. flavopictus consumes large amounts of termites, revealing the influence of prevailing ecological conditions. The small volume of ants in the diet of E. flavopictus and the high toxicity of its skin are not in agreement with the hypothesis of a causal relationship between skin toxicity and ant consumption.
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The understanding of feeding habits is important for anurans in general, both from an ecological and a phylogenetic perspective. For diurnal poison frogs belonging to the Dendrobatidae family, diet aspects play a crucial role in their defense and survival. Herein, we investigated feeding habits, foraging behaviour, and overall effects of habitat, sex, and body size on the diet of individuals of Ameerega braccata, a poorly known dendrobatid species. Specimens were observed and collected in the type-locality, Chapada dos Guimarães, and in the neighbouring municipality of Cuiabá, both in the State of Mato Grosso, Midwestern Brazil. The most important prey categories for A. braccata were Formicidae, Isoptera, and Acari, whose representatives were caught during active foraging. Individuals from Chapada dos Guimarães population consumed more Acari but fewer Isoptera than individuals from Cuiabá. Despite this, niche breadth values were narrow and similar for the two populations. Individuals from two distinct habitats (campo sujo and cerrado stricto sensu) showed differences in their diet, probably as an effect of differential prey availability. Females consumed more Isoptera than males. The number of prey categories used as food was not influenced by the variation of body size of the target species. However, the abundance and the volume of consumed Acari were statistically correlated with body size. The main results suggest that Ameerega braccata has a narrow niche breadth, as well as a specialised diet in ants, termites, and mites, which reinforces the hypotheses of close association between Acari consumption and the presence of skin toxic alkaloids, already found in other species of Dendrobatidae. Although differences in prey consumption between sexes are uncommon among poisonous frogs, differences in the diet composition between age classes, which probably reduce intraspecific competition, are frequently reported.
This study examines the morphological, taxonomic, ecological, and ontogenetic correlates of mite-eating (acariphagy) in anurans to increase our understanding of diet specialization in vertebrate "insectivores." In a review of the literature (Part I), mites were abundant in terrestrial habitats at many locations worldwide, yet mites are not commonly reported as prey in anuran diets. In a detailed study of tropical ground-dwelling anurans (Part II), the diets of all species included mites. In both the literature review and detailed study, mites constituted up to 45% of the diet (by number) of some species. In the paleotropics, at one montane cloud forest site in New Guinea, frogs ate mites in the same high proportions (45%) as they occurred in the substrate. In the neotropics, certain small anurans specialized on mites, in that they ate mites in higher proportions than occurred in the leaf litter (proportion of mites in the diet and in the environment was lower at these locations than at the New Guinea site). Neotropical mite specialists included juveniles of several species and adults of small dendrobatids in the genus Minyobates. Mites in the neotropics apparently constitute prey equivalent to ants and are included on the small end of the size continuum by species in the "ant-specialist" guild. We hypothesize that mites, like ants, present low costs of search and pursuit because they are abundant and slow-moving relative to anuran predators. The trade-off, however, is that these prey contain a higher proportion of chitin and are therefore costly to digest (e.g., require special enzymes, slow rate of passage) as primary prey. Nothing is known of the digestive physiology of anurans that specialize on mites and ants.
Poison frogs (Family Dendrobatidae) are common leaf litter inhabitants of New World tropical rainforests. The name of this group derives from several genera (especially Dendrobates, Minyobates, and Phyllobates) that are aposematically coloured and have toxic skin to varying degrees. Other species in the family, primarily the genus Colostethus, are cryptically coloured and non-toxic. Recent studies have revealed that the toxic compounds in the skin, which are lipophilic alkaloids, may have a dietary origin. Diets and associated characteristics, prey size, prey number, and niche breadth, of nine species in five genera, three of which have poisonous species, were examined. Interpretation of these characteristics in light of an independently constructed cladogram revealed the inclusion of a high percentage of Formicidae (ants) in the diets of toxic species. Although alkaloids have been reported in several insect groups, more alkaloids are known from ants than any other group. Species in the genus Dendrobates, which are poisonous and have many other derived characters, have diets composed of 50–73% ants, whereas percentages of ants used by non-toxic species in the genus Colostethus was 12–16%. Ants are the major prey category consumed by the five poisonous species considered in this study. In general, frogs separated into two groups. More basal groups with non-toxic skin and cryptic coloration had diets with low percentages of ants, low numbers of prey per individual, and high niche breadths, indicating inclusion of a broad range of prey categories in their diets. Species with poisonous skin and aposematic coloration had diets with large percentages of ants, large numbers of prey per individual, and low niche breadths, indicating diets with relatively few prey categories. Thus, diet, and the subsequent evolution of uptake systems for alkaloids, may be the primary character that led to the development of toxic skin and permitted aposematism, leading to radiation of poisonous species.
Thirteen species of anurans belonging to three families forage diurnally for arthropods in the leaf litter of the lowland rainforest at the Ro Llullapichis in Amazonian Per. This paper investigates the diets and patterns of coexistence in this group of ecologically similar species. All thirteen species use the forest floor habitat without apparent differentiation. Most species take prey in proportions significantly different from those occurring in the leaf litter and comprise two specialist guilds: dendrobatids and bufonids that eat hard-bodied, slow-moving arthropods such as ants and mites; and leptodactylids that eat soft-bodied, mobile arthropods, primarily orthopterans and large spiders. Dendrobates femoralis (Boulenger) is a generalist, taking prey in proportions not significantly different from those in the leaf litter. Within specialist guilds, body sizes of species vary and are correlated with the size of prey taken. Foraging behavior and predator defense also correlate with the type and sizes of prey taken. Ant specialists tend to be poisonous and active searchers, taking many small prey per day. Non-ant specialists are cryptic, sit-and-wait foragers that take few large prey per day. Similarity in diet within guilds tends tobe lowest in the dry season when food is less abundant, suggesting that food is in short supply in the dry season.