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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)

Authors:
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. http://www.zoologicalbulletin.de
https://doi.org/10.20363/BZB-2019.68.1.093
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
(Fig.1).Weconductedsixeldtrips(eachlastingfour
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
with5%lidocaine,xedin10%formalinandpreserved
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
urn:lsid:zoobank.org:pub:CBA156F4-E9AA-401C-B036-77C362CE1E89
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
1
Universidade Federal de Mato Grosso do Sul, Campus Aquidauana, 79200-000, Aquidauana, Mato Grosso do Sul, Brazil
2
Departamento de Química Biológica, Programa de Pós-graduação em Bioprospecção Molecular, Universidade Regional do
Cariri, 63105-00, Crato, Ceará, Brazil
3
Departamento de Biologia, Universidade Estadual do Centro-Oeste, 85040-080, Guarapuava, Paraná, Brazil
4
Instituto de Ciências Naturais, Humanas e Sociais, Universidade Federal de Mato Grosso – Campus Universitário de Sinop,
78557-267, Sinop, Mato Grosso, Brazil
4
Instituto Nacional de Ciência e Tecnologia de Estudos Integrados da Biodiversidade Amazônica – Núcleo Regional de Sinop,
Sinop, Mato Grosso, Brazil
5
Rua Clóvis n. 24, 79022-071, Campo Grande, Mato Grosso do Sul, Brazil
* Corresponding author: Email: fabricio_oda@hotmail.com
1
urn:lsid:zoobank.org:author:5821C96D-4D9E-4E1D-BE9B-C231B77D1AF3
2 urn:lsid:zoobank.org:author:349712B5-E1B2-4059-A826-58F081DD3A4D
3 urn:lsid:zoobank.org:author:E996AF2A-6CB7-4B73-8DEF-AB7C5EEE1AA0
4 urn:lsid:zoobank.org:author:ACFBA432-3220-4910-AFF5-8FF85053A872
5 urn:lsid:zoobank.org:author:626F6AE3-7D90-4500-BFDC-4E6F4E01B378
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
identiedtothelowesttaxonomiccategorypossible.We
used the Student’s t-test (t) to determine differences in
numeric percentage (N%) per prey category between
malesandfemales.Asnosignicantdifferencesbetween
sexes were found (t = 0.72, p > 0.05), we calculated the
numeric percentage per prey category for the pooled
stomachs.
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 (%)
Insecta
Formicidae 40 (22.6)
Coleoptera (both larvae and adults) 39 (22.0)
Diptera 29 (16.4)
Homoptera 17 (9.6)
Arachnida
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
95
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
Bodoquena,whichseemstoreecttheavailabilityvari-
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
sexes.
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
SpeciesLocalityaReference
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.
TheConselhoNacionaldeDesenvolvimentoCientícoeTec-
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
CientícoeTecnológico(grantn.88887.162751/2018-00).
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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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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.
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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.
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