A new nurse frog (Anura: Allobates) from Brazilian Amazonia with a remarkably fast multi-noted advertisement call

Abstract

Nurse frogs (Aromobatidae: Allobates) are probably the most extensively studied genus by taxonomists in Brazilian Amazonia. The southwestern portion of Amazonia is the most species-rich: as many as seven species may occur in sympatry at a single locality. In this study, we describe a new species of nurse frog from this region. The description integrates data from larval and adult morphology, advertisement calls and DNA sequences. Allobates velocicantus sp. nov. is distinguished from other Allobates mainly by the absence of hourglass-shaped dark marks on the dorsum and dark transverse bars on the thigh; a throat that is white centrally and yellow marginally; basal webbing on toes II and III; finger I longer than finger II; and an advertisement call composed of 66–138 pulsed notes with a note duration of 5–13 ms, inter-note intervals of 10–18 ms and a dominant frequency of 5,512–6,158 Hz. Tadpoles of the new species have 3–4 short, rounded papillae on the anterior labium, 16–23 papillae on the posterior labium, and a labial keratodont row formula 2(2)/3(1). This is the fifth species of Allobates described from the state of Acre, southwestern Brazilian Amazonia.

A new Amazonian species of Allobates Zimmermann & Zimmermann, 1988 (Aromobatidae) with a trilled advertisement call

“…nov. ): A. goianus calls have trills with a mean duration of 3.9 s and 2–41 notes emitted at 3.1–3.9 notes per second ( Carvalho, Martins & Giaretta, 2016 ); A. paleovarzensis trills of 0.72–3.02 s with 3–21 notes emitted at 6.97 notes/s ( Lima et al, 2010 ); A. tinae trills last 0.285–2.27 s (1.50 ± 0.45) with 2–9 notes (mode = 8) emitted at 5.34 notes/s ( Melo-Sampaio, Oliveira & Prates, 2018 ). Finally, A. velocicantus presented a similar trill duration of 1.87–2.89 s (2.49 ± 0.22), with 66–138 notes emitted at 51.2 ± 5.8 (38.4–56.8) notes/s ( Souza et al, 2020 ). Two species presented longer trills with more notes: A. bacurau has trills of 7–11 s with 60–81 notes ( Simões, 2016 ); and A. juami has trills of 2.5–5.09 s (4.51 ± 0.37) with 60–73 notes (65 ± 4) ( Simões et al, 2018 ).…”

“…The new species described here is only known to occur in ombrophilous forests from southern Brazilian Amazonia, in the boundary of the southern Pará state with northern Mato Grosso state, Brazil. Based on this restricted distribution and molecular phylogenetic affinities, we phenotypically compare the new species with all 31 Brazilian congeners (54.4% of the currently known genus diversity): Allobates bacurau Simões, 2016 , A. brunneus , A. caeruleodactylus ( Lima & Caldwell, 2001 ), A. caldwellae Lima, Ferrão & Silva, 2020 , A. carajas , A. conspicuus ( Morales, 2002 ), A. crombiei , A. femoralis , A. flaviventris Melo-Sampaio, Souza & Peloso, 2013 , A. fuscellus ( Morales, 2002 ), A. gasconi ( Morales, 2002 ), A. goianus ( Bokermann, 1975 ), A. grillicantus ( Moraes & Lima, 2021 ), A. grillisimilis , A. hodli , A. magnussoni Lima, Simões & Kaefer, 2014 , A. marchesianus ( Melin, 1941 ), A. masniger ( Morales, 2002 ), A. myersi , A. nidicola ( Caldwell & Lima, 2003 ), A. nunciatus Moraes, Pavan & Lima, 2019 , A. olfersioides , A. pacaas Melo-Sampaio et al, 2020 , A. paleovarzensis Lima et al, 2010 , A. subfolionidificans ( Lima, Sanchez & Souza, 2007 ), A. sumtuosus ( Morales, 2002 ), A. tapajos , A. tinae Melo-Sampaio, Oliveira & Prates, 2018 , A. trilineatus ( Boulenger, 1884 ), A. vanzolinius ( Morales, 2002 ), and A. velocicantus Souza et al, 2020 . The character states of the compared species are given in parentheses.…”

“…From A. bacurau , A. caeruleodactylus , A. caldwellae , A. conspicuus , A. fuscellus , A. grillicantus , A. grillisimilis , A. juami , A. masniger , A. nidicola , A. nunciatus , A. paleovarzensis , A. subfolionidificans , A. sumtuosus , A. tinae , A. trilineatus , A. vanzolinius , and A. velocicantus , A. paleci sp. nov. can be distinguished by have a light brown dorsum with dark brown hourglass mark ranging from the interorbital level to the urostyle region (dorsum without contrasting marks) ( Melin, 1941 ; Lima & Caldwell, 2001 ; Morales, 2002 ; Caldwell & Lima, 2003 ; Lima, Sanchez & Souza, 2007 ; Lima et al, 2010 ; Simões et al, 2013a ; Simões et al, 2013b ; Simões, 2016 ; Melo-Sampaio, Oliveira & Prates, 2018 ; Simões et al, 2018 ; Moraes, Pavan & Lima, 2019 ; Lima, Ferrão & Silva, 2020 ; Souza et al, 2020 ). Allobates paleci sp.…”

“…The number of species of Allobates Zimmermann & Zimmermann, 1988 has continuously increased during the last two decades ( e.g . Simões et al, 2018 ; Moraes, Pavan & Lima, 2019 ; Simões, Rojas & Lima, 2019 ; Souza et al, 2020 ; Jaramillo et al, 2021 ), but several phenotypically and molecularly lineages remain unnamed (see Simões, Lima & Farias, 2010 ; Grant et al, 2017 ; Fouquet, Vidal & Dewynter, 2019 ; Lima, Ferrão & Silva, 2020 ; Réjaud et al, 2020 ). Currently, the genus includes 58 species allocated into four groups: the Atlantic Forest group [one species, A. olfersioides ( Lutz, 1925 )], the trans-Andean group [two species, A. niputidea Grant, Acosta & Rada, 2007 and A. talamancae ( Cope, 1875 )], the colorful A .…”

A new nurse frog of the Allobates tapajos species complex (Anura: Aromobatidae) from the upper Madeira River, Brazilian Amazonia

“…Indeed, 18 of the 19 species of Allobates named since 2010 have been described through integrative taxonomy ( e.g. , Moraes, Pavan & Lima, 2019 ; Souza et al, 2020 ; Silva et al, 2022 ), while only one description was based solely on morphological characters ( Anganoy-Criollo, 2012 ). Although integrative taxonomy may be useful in contemporary treatments of any taxon ( Padial et al, 2010 ), it is an essential approach for deriving solid and reliable diagnoses of new species of Allobates , especially those that belong to species complexes ( Lima, Ferrão & Silva, 2020 ).…”