A new species of Colostethus (Anura, Dendrobatidae) from French Guiana with a redescription of Colostethus beebei (Noble, 1923) from its type locality

Two new species of Allobates of the trilineatus clade (Anura: Aromobatidae) from the Eastern Guiana Shield

The actual diversity of anurans occurring in Amazonia remains only partly described. This is notably the case of the species of the genus Allobates despite a fast rate of species description in this genus during the last decade. This increasing taxonomic effort has been particularly facilitated by the availability of DNA sequences throughout the region. These data suggest for instance the existence of three lineages in the Guiana Shield that may correspond to unnamed species. We examined morphology and calls of these putative species and compared them to related nominal species, which confirmed that two of these lineages not only differ genetically but also morphologically and bioacoustically. These two species are thus named and described herein. Allobates vicinus sp. nov. from northern Suriname forms a clade with another candidate species from southern Suriname and Northern Pará, (Brazil) and with A. granti that occurs in French Guiana. Allobates ripicolus sp. nov. occurs throughout the eastern Guiana Shield and is nested within the A. tapajos complex which otherwise occurs in southeastern Amazonia and comprises A. tapajos and A. kamilae, along with three additional candidate species.

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

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.

Comportamento territorial, vocalização e biologia reprodutiva de Allobates olfersioides (Anura: Aromobatidae)

RESUMO Em anfíbios a territorialidade, o cortejo elaborado e outras formas de comportamento, parecem estar mais associados a espécies que exibem o padrão de reprodução prolongado. A vocalização é um importante aspecto biológico relacionado à reprodução e ao comportamento social dos anuros. Este é o primeiro estudo com comportamento e vocalização da rã-foguete Allobates olfersioides (Lutz, 1925) e nós registramos em etograma o comportamento de territorialidade e corte, descrevemos e analisamos o seu repertório vocal e avaliamos a influência climática na atividade acústica da espécie. Ao todo 18 machos de A. olfersioides foram observados pelo método de animal focal, registrando todas as atividades individuais durante dez minutos. Adicionalmente, nós utilizamos o playback de um canto de advertência de macho adulto para analisar as respostas territoriais exibidas por indivíduos machos durante o trabalho. Para este anuro, registramos 11 comportamentos distintos e analisamos 14 cantos de anúncio que demonstraram que o canto de A. olfersioides é um canto simples e composto por uma única nota não pulsionada com duração média de 0,02s, intervalo médio entre cantos de 0,35s e frequência dominante média de 5,67kHz. O período de atividade vocal foi registrado durante quase todos os meses do estudo (novembro de 2015 a outubro de 2016), exceto novembro e dezembro, onde os indivíduos ficaram inativos quanto às atividades acústicas. Acreditamos que A. olfersioides apresente uma reprodução contínua (com duração de aproximadamente dez meses), devido à ausência de vocalizações durante os meses mais secos em novembro e dezembro. No que se refere às atividades comportamentais, A. olfersioides apresenta padrões de comportamento semelhantes a outras espécies de Aromobatidae, como também, o padrão territorialista já visto para o grupo, demonstrando a importância dos sinais acústicos e visuais.

The acoustic repertoire of the Atlantic Forest Rocket Frog and its consequences for taxonomy and conservation (Allobates, Aromobatidae)

The use of acoustic signals is a common characteristic of most anuran species to mediate intraspecific communication. Besides many social purposes, one of the main functions of these signals is species recognition. For this reason, this phenotypic trait is normally applied to taxonomy or to construct evolutionary relationship hypotheses. Here the acoustic repertoire of five populations of the genus Allobates from the Brazilian Atlantic Forest are presented for the first time, on a vulnerable to extinction Neotropical taxon. The description of males' advertisement and aggressive calls and a female call emitted in a courtship context are presented. In addition, the advertisement calls of individuals from distinct geographical regions were compared. Differences in frequency range and note duration may imply in taxonomic rearrangements of these populations, once considered distinct species, and more recently, proposed as a single species, Allobates olfersioides. Calls of the male from the state of Rio de Janeiro do not overlap spectrally with calls of males from northern populations, while the shorter notes emitted by males from Alagoas also distinguishes this population from the remaining southern populations. Therefore, it is likely that at least two of the junior synonyms should be revalidated. Similarities among male advertisement and female calls are generally reported in other anuran species; these calls may have evolved from a preexisting vocalization common to both sexes. Male aggressive calls were different from both the male advertisement and female calls, since it was composed by a longer and multi-pulsed note. Aggressive and advertisement calls generally have similar dominant frequencies, but they have temporal distinctions. Such patterns were corroborated with the Atlantic Forest Rocket Frogs. These findings may support future research addressing the taxonomy of the group, behavioral evolution, and amphibian conservation.

Quantitative acoustic analysis of the vocal repertoire of the golden rocket frog (Anomaloglossus beebei)

This study describes the vocal repertoire of the Guyanan golden rocket frog, Anomaloglossus beebei, a bromeliad specialist with biparental care. Using multivariate analyses of nine call properties, as well as the occurrence of nonlinear phenomena, three signal types were distinguished-advertisement, courtship, and aggressive calls. Although all three call types were composed of a short series of rapidly repeated pulses, advertisement calls were produced at higher amplitudes and had longer pulse durations than both courtship calls and aggressive calls. Courtship calls exhibited lower dominant frequencies than both advertisement and aggressive calls, which had similar dominant frequencies. Aggressive calls had more pulses per call, had longer intervals between calls, and occasionally contained one or two introductory pulses preceding the pulsed call. Several acoustic properties predicted aspects of the signaler's body size and condition. Our study demonstrates the reliability of human observers to differentiate the multiple call types of A. beebei based on hearing calls and observing the social context in which they are produced under field conditions.