Anuran amphibians are preyed on by vertebrates, invertebrates, and even carnivorous plants (Duellman and Trueb, 1994). Although anurophagy by spiders is relatively well documented in recent reviews (Lannoo, 2005; Menin et al., 2005; Toledo, 2005; Toledo et al., 2007), particularly in the Neotropics (Barej et al., 2009; Barbo et al., 2009; Maffei et al., 2010), most of them do not provide supplementary details (e.g., details of the predatory event, biometric information, etc.). Herein, we report on two successful events of predation (one of them detailing prey capture) and one attempt, all involving the same spider species preying on hylid frog species of the genus Dendropsophus.

On January 15th, 2012, at Parque Estadual da Serra do Mar (PESM), Núcleo Santa Virgínia, municipality of São Luís do Paraitinga, state of São Paulo, southeastern Brazil (23º20’10.32”S, 45º08’45.3”W; 820 ASL), we

recorded at 20:50 h a juvenile Thaumasia velox Simon, 1898 (Araneae: Pisauridae) trying to capture an adult Nova Friburgo Treefrog, Dendropsophus microps (Peters, 1872) (Anura: Hylidae) in a swamp, beside a trail of a forest floor 20 m far from one margin of the Paraibuna river. At the time, the frog managed to escape and swam away, but spider was captured (IBSP 163250, SVL = 9.32 mm leg span). On February 16th, 2012, we recorded at 21:05 h an adult female T. velox (IBSP 163250, SVL = 16.63 mm leg span) successfully capturing an adult female of D. microps (CFBH 32633, SVL = 18.09 mm, body mass = 0.42 g) at the same swamp (Fig. 1). Thirty minutes later, we registered another event of predation, by a male of T. velox (IBSP 163250, SVL = 12.02 mm leg span) upon a male of the hylid Lesser Treefrog, D. minutus (Peters, 1872) (CFBH 32632, SVL = 19.35 mm, body mass = 0.51 g), eight meters away from the other episode documented earlier on the same swamp (Fig. 2). We followed this predatory event entirely. The male D. minutus was calling on a plant (Poaceae) about 10 cm from the water surface, above where the spider was located. By the time the frog jumped into the water (probably due to the presence or approach of a member of our research team) the spider rapidly grabbed the frog’s dorsum by holding the frog with his pedipalps and chelicerae (Fig. 2). The frog tried to escape by pushing the spider with his legs, but three to five minutes later he was paralyzed. The spider kept the frog under the water surface during the duration of the event. Air and water temperatures were 19.1ºC and 18.3ºC, respectively, the air relative humidity was

Herpetology Notes, volume 7: 329-331 (2014) (published online on 26 May 2014)

Predation on two Dendropsophus species (Anura: Hylidae) by a pisaurid spider in the Atlantic forest, southeastern Brazil

Rafael Parelli Bovo1*, Eliziane Garcia de Oliveira1 and Lucas Nicioli Bandeira2

1 Programa de Pós-Graduação em Ciências Biológicas, Departamento de Zoologia, IB, Universidade Estadual Paulista “Júlio de Mesquita Filho”. Caixa Postal 199,13506-900 Rio Claro, SP, Brazil. email: rpbovo@gmail.com1; eliziane.garcia@gmail.com2

2 Programa de Pós-Graduação em Biologia Animal, Departamento de Zoologia e Botânica, IBILCE, Universidade Estadual Paulista “Júlio de Mesquita Filho”. 15054-000 São José do Rio Preto, SP, Brazil. email: azebandeira@gmail.com3

* corresponding author

Abstract. We report on two successful events of predation (and one attempt) on the hylid frogs Dendropsophus microps and D. minutus (Anura: Hylidae) by the spider Thaumasia velox (Araneae: Pisauridae) in the Brazilian Atlantic rainforest. Although never previously reported, our observations indicate that this spider species may constitute an important predator for small frogs of Brazilian Atlantic rainforest anuran communities.

Keywords. Amphibia, water spider, Neotropical region.

Rafael Parelli Bovo et al.330

Figure 1. A female pisaurid spider (Thaumasia velox) subduing a female Dendropsophus microps on the water surface of a swamp in São Luís do Paraitinga, state of São Paulo, southeastern Brazil. Photograph: Eliziane G. Oliveira.

Figure 2. A male pisaurid spider (Thaumasia velox) capturing a male Dendropsophus minutus eight meters away from the location of a previously recorded predation event. Photograph: Eliziane G. Oliveira.

Predation on two Dendropsophus species by a pisaurid spider in southeastern Brazil 331

89.8%, the sky was cloudless, and there was no wind (zero m/s2 at ten cm above the water surface). The swamp was 15 cm deep and 20 m in total length.

The genus Dendropsophus is well known as a common prey item for spiders. Indeed, members of three different spider families (Ctenidae, Pisauridae, and Lycosidae) are reported to prey on D. minutus (Bastos et al., 1994; Bernarde et al., 1999; Menin et al., 2005; Bocchiglieri et al., 2010), D. sanborni (Del-Grande and Moura, 1997), D. nanus (Pramuk and Alamillo, 2002), D. werneri (Oliveira et al., 2010), D. elegans (Santana et al., 2009), D. sarayacuensis (Rodrigues and Arruda, 2007), D. leucophyllatus (Jansen and Schulze, 2008), and D. melanargyreus (Moura and Azevedo, 2011). To this list, we add the first record of spider predation in D. microps and supplementary information for D. minutus. Predation by Thaumasia spiders was previously recorded for D. minutus (Bocchiglieri et al., 2010) and D. nanus (Pramuk and Alamillo, 2002), although, in these cases, the specific species of spider was not identified. Our observations of the predatory events described herein and the observed high abundance of T. velox in the habitats visited (though not quantified) suggests that this species may constitute an important opportunistic predator of post-metamorphic frogs in the Brazilian Atlantic rainforest.

Acknowledgements. We thank Antonio D. Brescovic for the identification of the spiders. Denis V. Andrade and Victor G. D. Orrico provided helpful suggestions on the manuscript. Financial support was provided by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). Collecting permit was issued by COTEC (SMA process number 260108-013.054/2011).

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Accepted by Mirco Solé