Herpetology Notes, volume 14: 657-660 (2021) (published online on 12 April 2021) Notes on the breeding behaviour of Elachistocleis helianneae Caramaschi, 2010 (Anura: Microhylidae) Jackson Cleiton Sousa and Carlos Eduardo Costa-Campos* The neotropical microhylid genus Elachistocleis Amplexus lasted about two hours (10:37–12:37 h) and Parker, 1927 comprises 19 species, distributed included five ovipositions in a single event. The female laid throughout the Neotropics from Panama to central approximately 30 eggs in each oviposition that floated on Argentina (Frost, 2020). Members of this genus are the water surface. Uninterrupted video was recorded for 2 terrestrial, active during both day and night, and usually h with a Sony HDR-CX 440 Full HD camera positioned found in lowland ecosystems and swampy open areas 1 m from the amplexed couple, using headlamps with red (Lima et al., 2012; Frost, 2020). However, there are still filters to minimize disturbance. We analysed 87 min of many species of microhylid for which basic aspects of recording until the oviposition was interrupted. The video their reproductive biology are unknown (e.g., Rodrigues recording was deposited at Fonoteca Neotropical Jacques et al., 2003; Thomé and Brasileiro, 2007; Altig and Vielliard (ZUEC-VID 790). Rowley, 2014; Pombal and Cruz, 2016; Elgue and After 2 h of recording, the couple remained in Maneyro, 2017). amplexus without further oviposition activity. The frogs Elachistocleis helianneae Caramaschi, 2010 is a and five of the clutches were collected and placed in small-sized frog (snout-vent length of 22.6–28.7 mm in plastic bags containing water; inside the plastic bag, the males, 29.3–36.4 mm in females) that is distributed in female continued to oviposit. The frogs and clutches the Brazilian states of Amazonas, Pará, Rondônia, and were preserved in 70% alcohol and 5% formaldehyde, Amapá, as well as in northeastern Bolivia (Caramaschi, respectively, and the number of eggs was counted in 2010; Costa-Campos and Freire, 2015). Adults breed the laboratory. The specimens are now housed in the during the rainy season, adopting temporary ponds in Herpetological Collection of Universidade Federal do open areas or near forest borders (Lima et al., 2012). Amapá, deposited with field numbers CECC 00543 Herein, we describe amplexus and oviposition of E. (male) and CECC 00550 (female and clutch). helianneae, based on field observations and video The E. helianneae male called frequently during the recordings. day (10:00–12:00 h) on the water surface, adopting We observed part of the mating behaviour of E. a semi-erect position, with his black vocal sac fully helianneae under natural conditions at the municipality inflated and contrasting with his yellow ventral of Santana, Amapá State, Brazil (0.0365°N, 51.1625°W, coloration. The lower half of his body was underwater, datum WGS84; elevation 26 m). The description is based with his hind feet sustained by submerged vegetation on one pair of frogs observed on 24 December 2016 (air composed of grasses. The female approached the male temperature 26.0°C, relative humidity 75.6%), found in slowly up to a distance of 15 cm, remaining in front a hole in the ground (2 m deep and 2 m wide) formed by of him with her body floating on the water. The male rainwater and maintained by emergent vegetation. We stopped calling and touched the female’s head with his also observed individuals of Adenomera hylaedactyla forelimbs, then moved into an axillary amplexus. The (Cope, 1868) calling at the edge of this hole. amplectant pair floated for 10–36 s (18.8 ± 10.4 s; n = 5) on the water surface, after which the male grasped the female and placed his cloaca behind the female cloaca (Fig. 1A). The female then immersed by dipping her 1 Laboratório de Herpetologia, Departamento de Ciências Bioló- head into the water and moved her legs in “swimming gicas e da Saúde, Universidade Federal do Amapá, Macapá, movements,” which forced the heads of both male and 68903-419 Amapá, Brazil. female underwater for 2–3 s (2.5 ± 0.7 s; n = 4). Both * Corresponding author. E-mail: [email protected] cloacas, previously submerged, rose above the water © 2021 by Herpetology Notes. Open Access by CC BY-NC-ND 4.0. surface (Fig. 1B). The male moved his body forward, 658 Jackson C. Sousa and Carlos E. Costa-Campos Figure 1. Breeding behaviour of Elachistocleis helianneae. (A) Amplectic couple floating on the water surface, showing the male in axillary amplexus with the female, placing his cloaca behind the female cloaca. (B) Female immersing her head into the water and moving her legs, producing “swimming movements.” The heads of both female and male remained underwater and the cloacas, previously submerged, rose above the water surface. (C) Male moving his body forward, hooking his legs under the female’s legs. (D) Female releasing eggs on the surface of water. Note that the female’s and the male’s legs started to extend to the sides. hooking his legs under the female’s legs (Fig. 1C), pigmented eggs (n = 1) with a dark black animal whereupon the female released 26–32 eggs (29.3 ± 3.0 pole and a whitish vegetal pole, both surrounded by a eggs; n = 3) on the surface of water (Fig. 1D) at intervals transparent gelatinous membrane. We recognize that of 11–41 s (22.5 ± 10.6 s; n = 5). number of eggs is based on an unnatural situation: a pair Altogether, the observed clutches (five clutches in a plastic bag. However, the couple deposited viable deposited in a natural environment + clutches produced eggs, which may indicate that this number of eggs by the female inside the plastic bag) contained 146 occurs in the natural environment. Notes on the Breeding Behaviour of Elachistocleis helianneae 659 Ours is the first breeding behaviour observation for Caramaschi, U. (2010): Notes on the taxonomic status of E. helianneae. So far, the breeding behaviour of E. Elachistocleis ovalis (Schneider, 1799) and description of five helianneae was poorly known because of the cryptic new species of Elachistocleis Parker, 1927 (Amphibia, Anura, Microhylidae). Boletim do Museu Nacional, Nova Serie, habits and explosive activity of the species, which is Zoologia 527: 1–30. limited to heavy rain (rainfall > 35 mm) and on a few Cordioli, L.A., Matias, V.S., Carvalho-e-Silva, A.M.P.T. (2019): subsequent days (2–3 days). Indeed, information about Ontogeny and reproductive aspects of Chiasmocleis lacrimae the natural history and the reproductive aspects of this (Anura, Microhylidae, Gastrophryninae) in an unspoiled frog was limited to the description of the advertisement Atlantic Forest area in the state of Rio de Janeiro, Brazil. call (Fonseca et al., 2012; Marinho et al., 2018) and of Herpetology Notes 12: 1037–1050. tadpoles (Dias-Souza et al., 2019). Costa-Campos, C.E., Freire, E.M.X. (2015): Distribution extension and geographic distribution map of Elachistocleis Our results indicate that E. helianneae is a typical helianneae (Anura: Microhylidae): new record for state of explosive breeder, with individuals congregating in Amapá, Eastern Amazon. Check List 11: 1747. ponds just after the first heavy rains at the beginning of Crump, M.L. (2015): Anuran reproductive modes: evolving the rainy season (Rodrigues et al., 2003; López et al., perspectives. Journal of Herpetology 49: 1–16. 2017; Ulloa et al., 2019). As result, females have larger Dias-Souza, M.R., Costa-Campos, C.E., Menin, M. (2019): The clutches during a breeding season than non-explosive tadpole of Elachistocleis helianneae Caramaschi, 2010 (Anura: breeders (Prado and Haddad, 2005; Elgue and Maneyro, Microhylidae). Zootaxa 4701: 594–600. Elgue, E., Maneyro, R. (2017): Reproductive biology in a 2017). Uruguayan population of Elachistocleis bicolor (Guérin- The reproductive behaviour of E. helianneae is similar Meneville, 1838) (Anura, Microhylidae). Cuadernos de to that described for other microhylid frogs (Pombal and Herpetología 31: 5–10. Haddad, 2005; Crump, 2015), with the oviposition of Fonseca, E.M., Lanna, F.M., Sant’Anna, A.C., Pereira, E.A., Dos aquatic eggs and exotrophic tadpoles in lentic water Santos, F.F., Neves, M.O., Mângia, S. (2012): The advertisement (Reproductive Mode 1 sensu Haddad and Prado, 2005). call of Elachistocleis helianneae Caramaschi, 2010 (Anura: Our results show that E. helianneae has a reproductive Microhylidae). Zootaxa 3559: 58–60. Frost, D.R. (2020): Amphibian Species of the World: an Online mode similar to those described for some species of Reference. Version 6.0. American Museum of Natural History, Chiasmocleis (Haddad and Hödl, 1997; Prado and New York. Available at: http://research.amnh.org/herpetology/ Haddad, 2005; Rodrigues et al., 2008; Menin et al., amphibia/index.html. Accessed on 1 December 2020. 2011; Cordioli et al., 2019) and other Elachistocleis Haddad, C.F.B., Hödl, W. (1997): New reproductive mode in (Prado and Haddad, 2005). anurans; bubble nest in Chiasmocleis leucosticta (Microhylidae). Our study adds to a growing body of knowledge on Copeia 1997: 585–588. the breeding biology of neotropical microhylid frogs, Haddad, C.F.B., Prado, C.P.A. (2005): Reproductive modes in frogs and their unexpected diversity in the Atlantic Forest of revealing additional reproductive behaviours, such as Brazil. Bioscience 55: 207–217. amplexus, fertilization, egg-laying, and clutch sizes. Lima, A.P., Magnusson, W.E., Menin, M., Erdtmann, L.K., However, other aspects of E. helianneae’s reproductive Rodrigues, D.J., Keller, C., Hödl, W. (2012): Guide to the Frogs biology, such as its mating system and the extent of its of Reserva Adolpho Ducke, Central Amazonia. Second Edition. parental care, remain unknown and require additional Manaus, Brazil, Instituto Nacional de Pesquisas da Amazônia. research. López, J.A., Antoniazzi, C.E., Lorenzón, R., Ghirardi, R.