Bioacoustics of Hyloscirtus albopunctulatus

Diagnosis. Characters in this section pertain to preserved specimens unless otherwise noticed. Coloration refers to live specimens. The most similar species to Hyloscirtus albopunctulatus living in the Amazon basin are H. maycu sp. nov. , H. elbakyanae sp. nov. , H. dispersus sp. nov. , H. phyllognathus , and H. torrenticola . Hyloscirtus albopunctulatus differs by having a white supralabial stripe (absent in H. elbakyanae sp. nov. ), a supratympanic fold (absent in all species except in H. dispersus sp. nov. ), a thick tarsal fold (rudimentary in H. maycu sp. nov. , H. elbakyanae sp. nov. , and H. phyllognathus ), small to inconspicuous subarticular tubercles in hands and feet (conspicuous in hands and feet in H. maycu sp. nov. , H. elbakyanae sp. nov. , and H. dispersus sp. nov. ; Fig. 11 ), inconspicuous supernumerary tubercles in hands and feet (conspicuous in hands in H. dispersus sp. nov. ), an absent calcar tubercle (present in H. dispersus sp. nov. and H. phyllognathus ), well-defined pericloacal spots (ill-defined or absent in H. maycu sp. nov. , H. elbakyanae sp. nov. , and H. torrenticola ), and a clam shell iris with black or sand dune reticulations (a clam shell iris with dark pinkish or leather reticulations in H. maycu sp. nov. and H. elbakyanae sp. nov. , pearl or pinkish iris with leather reticulations in H. dispersus sp. nov. and bronze iris in H. torrenticola , Fig. 12 ). The advertisement call of H. albopunctulatus has a rise time of 2.28 ± 0.80 s (shorter in H. maycu sp. nov. with 0.832 s and in H. elbakyanae sp. nov. with 0.57 ± 0.05 s ), a dominant frequency of 2149.84 ± 137.36 Hz and a fundamental frequency of 1214.12 ± 184.71 Hz (higher dominant frequency of 2795.41 ± 138.68 Hz and fundamental frequency of 2210.8–2924.2 Hz in Hyloscirtus dispersus sp. nov. ). Hyloscirtus torrenticola also has a higher dominant frequency of 2743.79 ± 48.22 Hz and a fundamental frequency of 2743.75 ± 48.16 Hz. Hyloscirtus albopunctulatus has a call duration of 0.051 ± 0.005 s (longer in H. dispersus sp. nov. with 0.11 ± 0.015 s ). Hyloscirtus albopunctulatus has an intercall duration of 0.30 ± 0.06 s (shorter in H. phyllognathus with 0.05 s and in H. torrenticola with 0.07 ± 0.007 s ) (Table 4 , Fig. 9 ; Melin 1941 ; Duellman and Altig 1978 ; Rivera-Correa 2016 ). Moreover, all males of H. albopunctulatus were registered calling from under rocks next to streams ( n = 5; Pontificia Universidad Católica del Ecuador 2024 ), while all males of H. dispersus sp. nov. have been found calling while perching in vegetation over streams ( n = 14; Pontificia Universidad Católica del Ecuador 2024 ).

Advertisement call. We analyzed 26 calls from seven individuals. Six males ( QCAZ 59813 , 59815, 59817 and three non-collected males) from Comunidad Zarentza, Llanganates National Park, Provincia Pastaza , on 17–24 February 2017 , air temperature 19–21 ° C, recorded by D. Velalcázar and D. Rivadeneira. One individual ( QCAZ 48503 ) from Reserva Río Bigal, Provincia Orellana , recorded by M. Read, on 22 May 2010 . The advertisement call consists of a single tonal note, repeated a highly variable number of times in a series of calls (Fig. 9 A ). We found from two to more than 70 consecutive calls before long silence periods. One male ( QCAZ 59815 ) called with short pauses during 4.08 s , broadcasting 926 calls. The average call duration is 0.051 + 0.005 s with an average inter-call interval of 0.30 ± 0.06 s . The average dominant frequency of the call is 2149.8 ± 137.36 Hz. Other call parameters are listed in Table 4 .

Definition. In this section, coloration and characters refer to preserved specimens unless otherwise mentioned, based on four adult females and 17 adult males , including the paralectotypes . Hyloscirtus albopunctulatus can be diagnosed by the combination of the following characters: (1) mean SVL 32.3 mm in adult males (range 30.3–35.5; n = 17) and mean SVL 37.8 mm in adult females (range 37.1–38.1; n = 4) (Suppl. material 1 : table S 5, Fig. 7 ); (2) white supralabial stripe present; (3) tympanum round, inconspicuous in males and distinct in females, supratympanic fold present and unpigmented; (4) white ulnar and tarsal folds present and thick; (5) subarticular tubercles varying from small to inconspicuous in hands and feet; (6) supernumerary tubercles inconspicuous in hands and feet; (7) calcar tubercle absent; (8) pericloacal spots well-defined; (9) all surfaces plain cream with a combination of black and white spots in the dorsum; (10) in life, dorsal surfaces and flanks olive green to yellowish green, covered with white spots and with or without sparce or clumped black spots; axillar and inguinal regions yellowish or blueish; venter and anterior and posterior surfaces of thighs yellow; other ventral surfaces silver, brownish or greenish; yellow pericloacal spots; webbing yellow orange; iris clam shell with black or sand dune reticulations; (11) the advertisement call consist of a single note, with a mean duration of 0.051 ± 0.005 s , a mean dominant frequency of 2147.84 ± 137.36 Hz and a fundamental frequency of 1214.12 ± 184.71 Hz. The call can be repeated consecutively for an indefinite number of times (2 –> 70) in a series of calls.