Rediscovery, redescription and identity of Pristimantis nebulosus (Henle, 1992), and description of a new terrestrial-breeding frog from montane rainforests of central Peru (Anura, Strabomantidae)

Abstract

The taxonomic status of the strabomantid frog species Pristimantis nebulosus (Henle, 1992), originating from the southern Cordillera Azul in central Peru, is investigated based on examination of the holotype and its comparison with freshly collected topotypic material. Following current standards, we provide a redescription of the holotype. It is in a rather poor state and exhibits certain damages and preservation artifacts, conditions that have hampered an allocation of this nominal taxon to any known living population of Pristimantis in the past. Our detailed specimen-to-specimen comparison provided morphological evidence for the conspecifity of the holotype and freshly collected topotypes. Molecular phylogenetic analysis, based on the mitochondrial 16S gene fragment places P. nebulosus in the P. conspicillatus species group, being closely related to P. bipunctatus and an undescribed candidate species from the Cordillera de Carpish. From both, P. nebulosus differs by considerable divergence in the 16S gene (p-distance 4.1–6.2%). Based on the specimens available, we provide an updated diagnosis for P. nebulosus, compare it to other species in the P. conspicillatus group and describe its advertisement call. In addition, we describe and name the closely related candidate species from the Cordillera de Carpish. It is sister to P. bipunctatus and P. nebulosus, but differs from both mainly by its tuberculate dorsal skin (versus shagreen) and divergence in the 16S gene (3.3–4.1%). We briefly discuss cryptic species diversity in the P. conspicillatus and P. danae species groups and provide justification for the description of a singleton species.

Diversification of the Pristimantis conspicillatus group (Anura: Craugastoridae) within distinct neotropical areas throughout the Neogene

“…The use of only mtDNA for species delimitation generates known pitfalls (Moritz et al, 2004), and thus this method only provides a first hypothesis that requires confirmation based on other lines of evidence such as nuDNA, bioacoustics and morphological data. Nevertheless, most cases of putative species boundaries based on mtDNA that have been tested turned out to be confirmed, representing well differentiated phenotypically and reproductively isolated species for instance in recent contributions in Pristimantis K€ ohler et al, 2022;Roberto et al, 2022).…”

“…One of them, the Pristimantis gr. conspicillatus, encompasses 47 currently recognized taxa occurring mainly at low and mid elevation in Amazonia but also in the Andes, the Atlantic Forest, the Dry Diagonal (Cerrado) and the trans-Andean forests (Choco, Central America) (Padial et al, 2014 updated from recent species descriptions: Padial et al, 2016;de Oliveira et al, 2020;Taucce et al, 2020;Acosta-Galvis et al, 2020;Acevedo et al, 2020;K€ ohler et al, 2022;Roberto et al, 2022 and preliminary results, Supplemental Appendix 1). The species richness of this species group seems particularly high in Western Amazonia notably along the Andean foothills.…”

Integrative reappraisal of the Amazonian nurse frogAllobates gasconi(Morales 2002) based on topotypical data, with implications for the systematics and taxonomy of a large species complex

“…On the other hand, revisiting topotypic localities to collect fresh material is a feasible alternative for those species with known and accessible type localities (e.g. Lima et al, 2009;Köhler et al, 2022). This approach also presents opportunities to collect additional data to integrate with molecular evidence, such as advertisement calls and larval morphology; two valuable sources of diagnostic characters used in contemporary anuran taxonomy.…”