Herpetology Notes, volume 12: 829-831 (2019) (published online on 07 August 2019)

Adults of goeldii (Baumann, 1912) (Anura: ) preying upon tadpoles supports the species’ cannibalism

Dener das Neves da Silva1,*, Paulo Nogueira-Costa2,3, Felipe Cesar Barros da Rosa1, and Ana Maria Paulino Telles de Carvalho-e-Silva1

Cannibalism represents different survival strategies in Specimens of the genus are extremely rare in scientific natural populations. This behaviour can promote both collections due to restricted geographical ranges, cryptic direct benefits such as being an alternative food source behaviour (Giaretta et al., 1993; Melo et al., 1995) and when preferred ones are sparse, and indirect benefits low-density populations (Pombal et al., 2003). They are such as reducing competition among co-specific very agile , exhibiting a rapid response of diving individuals, by consuming the offspring of a competitor in lotic waters when disturbed, reducing the chance to via oviphagy or infanticide, or by eliminating future be captured (Miranda-Ribeiro, 1923; Izecksohn and competitors for food and reproduction (Polis, 1981; Gouvêa, 1985). Funnel traps have been used to capture Cooper et al., 2015). In anurans, cannibalism is a well- aquatic larvae and adults (Richter, 1995; known behaviour observed in spawnings, tadpoles and Buech and Egeland, 2002). However, this method is post-metamorphic individuals (McDiarmid and Altig, more successful for larval sampling compared to that of 1999; Silva et al., 2005; Pirani et al., 2010; Jancowski juveniles and adults (Adams et al., 1997). and Orchard, 2013). Recently, Silva et al. (2018) registered a great The genus Megaelosia Miranda-Ribeiro, 1923 prevalence of dekeratinised mouthparts in M. goeldii presents large-sized species, associated with lotic sites tadpoles and its association with the presence of the (Giaretta et al., 1993). All seven species of the genus fungus Batrachochytrium dendrobatidis, in which they are restricted to a limited area of the Atlantic Rainforest, warned for the urgency of further research that explores in the southeastern Brazil: M. apuana Pombal, Prado the biology of Megaelosia. Herein we describe the and Canedo, 2003; M. bocainensis Giaretta, Bokermann capture of three adult individuals and Haddad, 1993; M. boticariana Giaretta and Aguiar, using funnel traps and report on adult cannibalism of 1998; M. goeldii (Baumann, 1912); M. jordanensis this species on its larvae. (Heyer, 1983); M. lutzae Izecksohn and Gouvêa, 1985 We conducted the study in the Serra dos Órgãos and M. massarti (De Witte, 1930). National Park (PARNASO), in the municipality of Teresópolis, Rio de Janeiro State, Brazil. We made the funnel traps with plastic bottles (5 L) with their tops inverted and baited with tuna or sausage. We left the traps overnight for approximately ten hours in a 1 Laboratório de Biossistemática de Anfíbios, Departamento sheltered region of the Paquequer River (22º27’07’’S, de Zoologia, Instituto de Biologia, Centro de Ciências Biológicas e da Saúde, Universidade Federal do Estado do 43º00’03’’W). Rio de Janeiro, 22290-240, Rio de Janeiro, Rio de Janeiro The use of funnel traps for tadpole sampling has been State, Brazil. used successfully for many years by our team, mainly 2 Museu de Biodiversidade Tauari, Universidade Federal do Sul for capturing species that occupy deep and flowing e Sudeste do Pará, Unidade III, 68507-590, Marabá, Pará stream regions, such as M. goeldii (Silva et al., 2018). State, Brazil. However, despite the high efficiency of these traps for 3 Departamento de Vertebrados, Museu Nacional, Universidade Federal do Rio de Janeiro, 20940-040, Quinta da Boa Vista, larval sampling at PARNASO (A. Carvalho-e-Silva, Rio de Janeiro, Rio de Janeiro State, Brazil. pers. obs.), records of adult individuals were obtained * Corresponding author. E-mail: [email protected] only for M. goeldii (this study). 830 Dener das Neves da Silva et al.

In total, we collected three adults of M. goeldii over the and Trichomycterus fish from the same adult capture years. We transported the individuals to the laboratory site, in addition to nasus (Lichtenstein, 1823) and measured the snout-vent length (SVL) with a digital tadpoles from the Tijuca National Park, Rio de Janeiro, calliper (accuracy 0.01 mm). After the measurements and Brazil and we observed for a period of eight to ten hours experiments (see below), we anesthetised the specimens per day of experiment. The captive M. goeldii adult with 5% lidocaine, fixed in 10% formalin and preserved preyed upon the fish and tadpoles, including M. goeldii in 70% ethanol. They were subsequently registered and tadpoles, after the first 24 hours of the experiment. The stored at the Amphibian Collection of the Universidade attacks always occurred during daytime, in which the Federal do Estado do Rio de Janeiro (UNIRIO). The first stood still, submerged, waiting for the prey to adult was captured on 21 August 2005 (male, SVL = approach, and quickly attacked, propelled by its hind 86.6 mm, UNIRIO 2224). It was completely submerged legs, swallowing the prey rapidly. in the trap and the bait used for anuran attraction was Our data reinforce that M. goeldii presents a inside its oral cavity. The second capture occurred on generalised diet, such as other species of the family 25 November 2016 (male, SVL = 91.42 mm; UNIRIO Hylodidae (M. massarti, M. apuana, H. nasus, H. 5998). Inside the trap we also found M. goeldii tadpoles, phyllodes, gaudichaudii and C. which displayed lesions and regions with no skin. We schmidti; Giaretta et al., 1993; Almeida-Gomes et al., investigated the stomach contents of the adult, and 2007; Caldart et al., 2012; Machado et al., 2016; Alves tissue fragments presenting a similar coloration to the and Toledo, 2017). This had been previously reported by aforementioned tadpoles were found. The third capture Giaretta et al. (1993), who cited that M. goeldii stomach occurred on 31 March 2018 (female, SVL = 93.12 mm, contents included cockroaches (Dictyoptera), beetles UNIRIO 6208). The individual was photographed both (Coleoptera), caterpillars (Lepidoptera), earthworms inside and outside the trap (Fig. 1). The funnel trap (Oligochaeta), leaves and branches. In a field experiment, also contained M. goeldii tadpoles and fish belonging Giaretta et al. (1993) also noticed predation on other to the genus Trichomycterus Velanciennes, 1832. In the anuran adults belonging to the Hylidae, Hylodidae and laboratory, we analysed the M. goeldii stomach contents Brachycephalidae families. However, this is the first and found pieces of the bait (sausage) and fragments of report of adults preying upon tadpoles in M. goeldii and insect larvae (order Megaloptera) exoskeletons. in the family Hylodidae, not only of different species The first captured male (UNIRIO 2224) was taken to but also the same species. Although this was only the laboratory and kept alive for five days in a 45-liter observed in the laboratory and in one trap, we speculate aquarium. We placed stones in the bottom and used that anuran larvae are also included as M. goeldii food a submerged pump to more accurately simulate the items, since they use food resources found in both the natural environment. We also added M. goeldii tadpoles aquatic and terrestrial environments.

Figure 1. Adult female of Megaelosia goeldii (UNIRIO 6208) inside a funnel trap (a), and outside the trap (b). Megaelosia goeldii preying upon tadpoles supports the species’ cannibalism 831

In this sense, we propose that cannibalism is an Izecksohn, E., Gouvêa, E. (1985): Nova espécie de Megaelosia opportunistic feeding habit in M. goeldii, although more de Itatiaia, Estado do Rio de Janeiro (Amphibia, Anura, accurate observations are required in order to determine Leptodactylidae). Arquivos da Universidade Federal Rural do Rio de Janeiro 8: 17–22. whether cannibalism is present in natural populations. Jancowski, K., Orchard, S.A. (2013): Stomach contents from We believe that the use of funnel traps with the presence invasive American bullfrogs Rana catesbeiana (Lithobates of attractive baits may enhance capture success of catesbeianus) on southern Vancouver Island, British Columbia, Megaelosia species, both tadpoles and adults. Canada. NeoBiota 16: 17–37. Machado, A.O., Winck, G., Dorigo, T.A., Rocha, C.F.D. (2016): Acknowledgements. We thank Sergio Potsch (UFRJ) and Diet, diel activity pattern, habitat use, and reproductive effort of students of the Laboratório de Biossistemática de Anfíbios (Anura: Hylodidae) in one of the world’s largest – LABAN (UNIRIO) for their help with field work, Luiz urban parks (Tijuca National Park), southeastern Brazil. South Norberto Weber for the pre-peer review, and Amanda Alves American Journal of Herpetology 11: 127–135. Marinho (UNIRIO) for her help with English revision. We also McDiarmid, R.W., Altig, R. (1999): Tadpoles: The Biology of thank IBAMA/RAN for providing our collecting license (number Anuran Larvae. Chicago, USA, University of Chicago. 13256-1). Melo, A.S., Recco-Pimentel, S.M., Giaretta, A.A. (1995): The karyotype of the stream dwelling Megaelosia massarti References (Anura, Leptodactylidae, Hylodinae). Cytologia 60: 49–52. Miranda-Ribeiro, A.D. (1923): Elosia, Tsch. e os gêneros correlatos. Adams, M.J., Richter, K.O., Leonard, W.P. (1997): Surveying and Revista do Museu Paulista 13: 813–821. monitoring using aquatic funnel traps. Sampling Pirani, R.M., Silva, E.T., Feio, R.N. (2010): Tadpole cannibalism amphibians in lentic habitats: methods and approaches for the in Leptodactylus cunicularius Sazima & Bokermann, 1978 Pacific Northwest. Northwest Fauna 4: 47–54. (Anura, Leptodactylidae) at a temporary stream in Southeastern Alves, G.A., Toledo, L.F. (2017): Food items in the rheophilic Brazil. Herpetology Notes 3: 359–360. Torrent Frog Megaelosia apuana (Anura; Hylodidae). Polis, G.A. (1981): The evolution and dynamics of intraspecific Herpetology Notes 10: 535–536. predation. Annual Review of Ecology and Systematics 12: Almeida-Gomes, M., Hatano, F.H., Sluys, M.V., Rocha, C.F.D. 225–251. (2007): Diet and microhabitat use by two Hylodinae species Pombal Jr, J.P., Prado, G.M., Canedo, C. (2003): A new species (Anura, ) living in sympatry and syntopy in a of giant torrent frog, genus Megaelosia, from the Atlantic Rain Brazilian Atlantic Rainforest area. Iheringia, Série Zoologia 97: Forest of Espírito Santo, Brazil (Amphibia: Leptodactylidae). 27–30. Journal of Herpetology 37: 453–466. Buech, R.R., Egeland, L.M. (2002): Efficacy of three funnel Richter, K.O. (1995): A simple aquatic funnel trap and its traps for capturing amphibian larvae in seasonal forest ponds. application to wetland amphibian monitoring. Herpetological Herpetological Review 33: 182–185. Review 26: 90–91. Caldart, V.M., Iop, S., Bertaso, T.R.N., Cechin, S.Z. (2012): Silva, W.R., Giaretta, A.A., Facure, K.G. (2005): On the natural Feeding ecology of (Anura: Hylodidae) history of the South America pepper frog, Leptodactylus in Southern Brazil. Zoological Studies 4: 484–493. labyrinthicus (Spix, 1824) (Anura: Leptodactylidae). Journal Cooper Jr, W.E., Dimopoulos, I., Pafilis, P. (2015): Sex, age, and Natural History 39: 555–566. population density affect aggressive behaviors in island lizards Silva, D.N., Rosa, F.C.B., Carvalho-e-Silva, A.M.T. (2018): promoting cannibalism. Ethology 121: 260–269. Ontogeny and behavioural aspects of the tadpoles of Megaelosia Giaretta, A.A., Bokermann, W.C., Haddad, C.F. (1993): A review goeldii (Baumann, 1912) (Amphibia, Anura, Hylodidae). of the genus Megaelosia (Anura: Leptodactylidae) with a Herpetology Notes 11: 629–639. description of a new species. Journal of Herpetology 27: 276– 285.

Accepted by Renato Nali