Herpetology Notes, volume 9: 323-324 (2016) (published online on 06 December 2016)

Predation on egg clutch of Bokermannohyla circumdata (Anura: ) by the crab���� Trichodactylus fluviatilis (Crustacea: Trichodactylidae)

Paulo Nogueira-Costa1,*, Patrícia Almeida-Santos1, Juliana L. Segadilha2 and Carlos Frederico D. Rocha1

The eggs of constitute an important protein from the states of Pernambuco to Rio Grande do source for several groups of vertebrate and invertebrate Sul (Magalhães, 2003). Trichodactylus fluviatilis is organisms, and among the invertebrates, the arthropods considered an omnivorous species that feeds on plant represent the main predators of amphibians eggs and material, invertebrates, tadpoles, treefrogs and toads embryos (Wells, 2007). The consumption of (Magalhães, 2003; Mageski, 2013; Segadilha and Silva- protein contributes to the development of diet-generalist Soares, 2015). arthropods that may consume both plant and animal During a field work held between 9 and 13 February matter, such as caddisflies and crustaceans (Magalhães, 2016 at the Parque Nacional da Serra dos Órgãos, 2003; Winterbourn, 1971). The crustaceans are amongst Teresópolis, Rio de Janeiro, Brazil, we observed a the principal groups of arthropods known to consume reproductive event of B. circumdata in which 12 males vertebrates (McCormick and Polis, 1982), including were in calling activity in a small pond of approximately amphibians (Wells, 2007). Here, we report a predation 70 x 40 cm (Fig. 1A), while eight females remained event by the crab Trichodactylus fluviatilis Latreille, perched on the vegetation (about 60 cm above the 1828 on an egg clutch of Bokermannohyla circumdata ground) around the same reproductive site. We returned (Cope, 1870), a hylid that occurs in mountain to the pond in the next night and found it filled with regions of the Atlantic Rainforest of the Brazilian states eggs, and we observed an individual of Trichodactylus of Espírito Santo, Minas Gerais, Bahia, Rio de Janeiro, fluviatilis feeding on the newly deposited eggs (Fig. São Paulo, and Santa Catarina (Frost, 2016). 1B). At that time, the adults of B. circumdata were no Bokermannohyla circumdata has aquatic eggs which longer present in pond. are laid in basins, either natural or constructed by Animal protein is part of the diet of T. fluviatilis, conspecific males, which are subsequently flooded, which may include (Mageski, 2013; Segadilha carrying the exotrophic tadpoles to nearby lentic or lotic and Silva-Soares, 2015) and tadpoles (Motta-Tavares, watercourses in which they complete the development et al., 2015). In the study area, T. fluviatilis inhabits (Haddad and Prado, 2005). The freshwater nocturnal the same spawning sites of B. circumdata, so this crab Trichodactylus fluviatilis is endemic to altitude crab may represent an important predator of the eggs streams of the Atlantic Rainforest, widely distributed and tadpoles of this frog species. The mortality rate of eggs and embryos of amphibians caused by arthropods varies widely, reaching up to 100% in some instances (Howard, 1978). Although our observation indicate that T. fluviatilis could be a source of mortality to B. 1 Departamento de Ecologia, IBRAG, Universidade do Estado circumdata, at this point it is not possible to infer on do Rio de Janeiro, Rua São Francisco Xavier 524, Maracanã, the role of this crab on the dynamics of B. circumdata 20550-019, Rio de Janeiro, RJ, Brazil. population. However, in subsequent observations we 2 Departamento de Invertebrados, Laboratório de Carcinologia, observed that adults of B. circumdata continued to use Museu Nacional, Universidade Federal do Rio de Janeiro, Quinta da Boa Vista S/N, 20940-040, Rio de Janeiro, Rio de the same pond for breeding. Indeed, although we have Janeiro, Brazil. not counted the total number of eggs in the set of clutches, * Corresponding autor e-mail: [email protected] after two days of observation there was no apparent 324 Paulo Nogueira-Costa et al.

Acknowledgements. PNC and PAS thanks the Fundação de Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) for a Post-doc grant (processes E- 26/201.760/2015, E-26/201.829/2015 and E-26/101.412/2014). CFDR received research grants from CNPq (processes 304791/2010-5, 472287/2012-5 and 302974/2015-6) and FAPERJ through “Cientistas do Nosso Estado” Program (processes E- 26/102.765/2012 and E-26/202.920/2015). We are grateful to the Instituto Chico Mendes for the license (Sisbio nº 51410-1).

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