Short Notes 197 The tadpole and advertisement call of Physalaemus aguirrei Bokermann, 1966 (Amphibia, Anura, Leptodactylidae) Bruno V.S. Pimenta, Carlos Alberto Gonçalves Cruz Museu Nacional/UFRJ, Departamento de Vertebrados, Quinta da Boa Vista, 20940-040, Rio de Janeiro, RJ, Brazil e-mail: [email protected]; [email protected] The neotropical frog genus Physalaemus is currently composed of 41 valid species (Frost, 2002) arranged in four groups (Lynch, 1970). The Physalaemus cuvieri group is the most diversified, with 20 species occurring from northern to southern South America (Frost, 2002). Information about tadpoles of nine species and vocalizations of fifteen species of this group are available in literature (see Bokermann, 1962, 1966a, 1966b, 1967; Barrio, 1964, 1965; Langone, 1989; Heyer et al., 1990; Rossa-Feres and Jim, 1993; Duellman, 1997; Perroti, 1997; Cannatella et al., 1998; Tárano, 2001). However, Physalaemus aguirrei is a poorly known species of this group, occurring in the Atlantic Forest in the states of Espírito Santo and Bahia, Brazil (Van Sluys, 1998; Frost, 2002). According to Bokermann (1966a), this species can be found dwelling on the forest floor litter but breeds in temporary ponds in open habitats. Feio et al. (1999) pointed out that P. aguirrei, P. maximus, P. olfersii,andP. soaresi could compose a new species group, due to morphological similarities, and their forest breeding habits but they lacked necessary evidence to confirm this suggestion. Herein, we follow Lynch’s (1970) organisation of the P. cuvieri group. The purpose of this paper is to provide information on tadpole morphology, advertisement call structure and habitat of P. aguirrei. Tadpoles were obtained from a foam nest collected in a temporary pond inside the forest at Parque Nacional Descobrimento (17◦06S, 39◦20W), Municipality of Prado, southern region of the State of Bahia, Brazil, on 22 April 2002. The nest was partially degraded and had a small number of embryos inside, indicating that oviposition had not occurred recently. The tadpoles were reared in laboratory. Seven tadpoles at stage 36 and two at stage 37 (Gosner, 1960) were preserved in 5% formalin and deposited at Museu Nacional, Rio de Janeiro (MNRJ 30591). Measurements (table 1) were made with an ocular grid and a caliper. The terminology we use follows Altig and Johnston (1986) and Johnston and Altig (1986). Advertisement calls were recorded with a Sony TCD-D8 DAT-recorder with a Sennheiser K6/ME66 micro- phone set, on the same date and locality where tadpoles were collected. Sonograms were analyzed with the soft- ware Avisoft-Sonagraph Light 1, version 2.7. Vocalizations were digitalized and edited at a sampling frequency of 22 KHz, FFT with 256 points, and 16 bit resolution. Air temperature was recorded with a digital thermometer to the nearest 0.1◦C. Terminology follows Duellman (1970). Description of the tadpole. Stages 36-37 (Gosner, 1960). Mean total length 20.6 mm (16.6-25.4 mm; n = 9). Body robust, oval in dorsal and ventral views, elliptical in lateral view (fig. 1A, B, C); snout rounded in dorsal and lateral views; body length about 40% (39- 43%) of total length; body width approximately 70% (62-80%) of body length. Nostrils © Koninklijke Brill NV, Leiden, 2004 Amphibia-Reptilia 25: 197-204 Also available online - www.brill.nl 198 Short Notes Table 1. Mean (x)¯ , range and standard deviation (s) of measurements (in mm) of Physalaemus aguirrei tadpoles (n = 9; stages 36-37). x¯ Range s Total length 20.6 16.6-25.4 3.50 Body length 8.2 7.9-8.8 0.28 Body width 5.7 5.1-6.5 0.48 Body height 4.5 3.8-5.3 0.49 Tail length 12.4 8.5-16.6 3.29 Tail height 4.0 3.6-4.6 0.33 Distance nostril-snout 1.2 0.9-1.6 0.22 Distance eye-nostril 1.0 0.8-1.2 0.12 Interorbital distance 2.6 2.5-2.8 0.10 Internostril distance 0.9 0.8-1.0 0.05 Eye diameter 1.1 1.0-1.2 0.08 Oral disc width 2.2 1.8-2.5 0.21 large, nearly round, located and oriented dorsally, closer to eyes than to snout; internostril distance about 35% of interocular distance; eyes located dorsolaterally; eye-nostril distance about 89% of eye diameter; spiracle single, sinistral, short and projected, opening at the end of the second third of body length and posterodorsally oriented; vent tube medial, wide and long, attached to ventral fin, with opening oriented posteriorly (fig. 1C). Tail with approximately 60% of total length, with nearly the same height of body; tail musculature moderated; dorsal fin extending onto the posterior third of body; ventral fin wide arched, narrower than dorsal, that is nearly rectilineal; tail tip slightly directed upwards (fig. 1A). Oral disc anteroventral, laterally emarginated, its width approximately 38% of body width; one series of marginal papillae in the upper lip, interrupted by a wide medial gap; lower lip with two emarginations; marginal papillae of medial margin have their bases in one series, but with alternate papillae projected anteriorly and posteriorly, emulating a double row; margins on each side of the emarginations with one series of marginal papillae and one series of submarginal papillae; labial tooth row formula 2(2)/3(1). The two anterior and the first posterior teeth rows have approximately the same length; second posterior teeth row slightly shorter than first, and third posterior teeth row with nearly half length of first; upper jaw sheath arch-shaped and lower sheath “V”-shaped (fig. 1D). Color of tadpole in 5% formalin: Body translucent with many brown spots on dorsum; two or three weakly pigmented brown transverse stripes on the dorsal surface of tail, lateral surfaces with scattered brown dots; fins translucent with brown dots, more abundant on dorsal fin; legs with brown spots on dorsal surfaces. A brown blotch between the eyes, extending to the middle of body. Advertisement call consisted of a single note with a fundamental frequency and seven harmonics between 0.43 and 4.73 kHz, with descendent frequency modulation (fig. 2A). The mean duration of the advertisement call was 0.23 s (s = 0.01, range = 0.21-0.25, n = 55 calls of one male) (fig. 2B), and the mean intercall interval (defined here as the time from the end of one call to the beginning of the next call) was 1.22 s (s = 0.80, Short Notes 199 Figure 1. Tadpole of Physalaemus aguirrei, stage 37 of Gosner (1960): (A) lateral view; (B) dorsal view; (C) ventral view (scale = 5 mm); (D) oral disc (scale = 1 mm). range = 0.65-6.57, n = 55 calls of one male). Fundamental frequency was about 0.43 and 1.03 kHz; the dominant frequency was 3.10 kHz, corresponding to the sixth harmonic (fig. 2C); the eighth harmonic ranged from 3.53 to 4.73 kHz. Foam nests and tadpoles of P. aguirrei and P. signifer were found in the same pond. Physalaemus signifer tadpoles are smaller (maximum total length 17.5 mm on stage 36, n = 13), have no emarginations on lower lip, and posterior teeth rows with approximately the same length. Adults diverged spatially on calling and oviposition sites: males of P. signifer were calling under leaf litter on humid ground, 1.0-3.0 meters away from the edges of the pond, whereas males of P. aguirrei were calling hidden under fallen trunks and in small water-filled holes on the edges of the pond; nests of P. signifer were on humid ground at the edges of the pond, partially or completely covered by leaf detritus (cf. Weber and 200 Short Notes Figure 2. (A) Sonogram, (B) waveform, and (C) spectrogram of the advertisement call of Physalaemus aguirrei; recorded at Parque Nacional Descobrimento, Prado, Bahia, Brazil on 22 April 2002, 06:51 PM. Air temperature = 26.6◦C. Unvouchered specimen. Carvalho-e-Silva, 2001; Wogel et al., 2002), whereas the nests of P. aguirrei were floating on the water, anchored by emergent vegetation. Short Notes 201 The P. cuvieri group is extremely heterogeneous in external tadpole morphology, presenting no larval synapomorphies to define the group (Langone, 1989; Perroti, 1997). The tadpole of P. aguirrei is distinguished from the others known of the P. cuvieri group by differences in size, nostrils shape, labial tooth row formula, arrangement and distribution of marginal papillae, jaw shape, spiracle position and vent tube orientation. Data about the tadpole of P. aguirrei and other species of this group, were obtained from Bokermann (1962), Barrio (1964), Langone (1989), Rossa-Feres and Jim (1993), Duellman (1997), and Perroti (1997), and are summarized in table 2. The labial tooth row formula of P. cuvieri is presented by Heyer et al. (1990) as 2(2)/3(1) and by Perroti (1997) as 2(2)/2. The latter work cites Bokermann (1962) as the source of this information. The oral disc drawn by Bokermann (1962), however, shows the 2/3(1) formula, as cited by Rossa-Feres and Jim (1993). It seems that some aspects of the oral morphology of this species vary between populations. Bokermann (1962) shows a medial gap on the lower lip, while Heyer et al. (1990) show three gaps. Rossa-Feres and Jim (1993) also mentioned the presence of a ventral gap in the oral disc of P. gracilis, while it is absent according to Perroti (1997). Both cited Langone (1989), whose research shows no ventral gap. Bokermann (1966a) described the advertisement call of P. aguirrei with a fundamental frequency and seven harmonics, an intercall interval of 0.5-0.7 s, and a dominant frequency between 2.0 and 3.0 kHz, corresponding to the third to seventh harmonics.