Cryptic diversity in the Hypsiboas semilineatus species group (Amphibia, Anura) with the description of a new species from the eastern Guiana Shield

Abstract

We used molecular and morphological data to investigate the hidden diversity within the Hypsiboas semilineatus species group, and more specifically within H. geographicus, an allegedly widespread species in northern South America. As a result, the identity of H. geographicus was clarified, several candidate species were detected and one of them, from the eastern Guiana Shield, is described herein as a preliminary step to resolve the taxonomy of the group. Hypsiboas diabolicus sp. nov. is mainly distinguished from closely-related species by an acuminate snout in lateral view, well-developed webbing between fingers and toes, and unspotted carmine/crimson colouration on the concealed surfaces of legs, feet and hands in life. The tadpole of the new species is described and is characterized by a large A-2 gap, a mostly single row of large marginal papillae, and a dark brown to black colouration. We also describe the advertisement call of the new species, which is defined as a soft call consisting of short clusters of 2-3 chuckles with a dominant frequency ranging between 1.11-1.19 kHz. Hypsiboas diabolicus sp. nov. is currently known only from the eastern Guiana Shield, and is probably endemic to that region. The new species' range overlaps broadly with another candidate species referred to as H. aff. semilineatus 1. Our preliminary results stress out a high cryptic diversity in that species group and the need for a formal redescription of Hypsiboas geographicus based on more topotypic material than what is currently available to properly sort out the taxonomic status of several lineages in that clade.

Four new species of Pristimantis Jiménez de la Espada, 1870 (Anura: Craugastoridae) in the eastern Amazon

“…Studies indicate that in the last 250 years of taxonomic classification only 14% of all terrestrial species have been described [56]. Our results are part of a broad set of evidence that indicates that the Neotropical biodiversity, particularly through the Amazon, cannot be trivialized [57][58][59][60][61][62].…”

The use of bioacoustics in anuran taxonomy: theory, terminology, methods and recommendations for best practice

“…When advertisement calls are described for species that have already been named, it is recommendable to obtain recordings from their type locality (as well as obtaining topotypic voucher specimens), as this increases the chances of actually describing the call of a particular nominal species. However, in the latter case, careful morphological comparisions of newly collected call vouchers and original type specimens is warranted, as (cryptic) diversity at a single locality can be unexpectably high, particularly in the tropics (e.g., Jansen et al 2011;Gehara et al 2014;Fouquet et al 2016).…”

Amended diagnosis and redescription of Pristimantis marmoratus (Boulenger, 1900) (Amphibia: Craugastoridae), with a description of its advertisement call and notes on its breeding ecology and phylogenetic relationships

“…Too brief descriptions contribute to the confusion among morphologically similar taxa and make new species descriptions more challenging (see e.g., example Kok et al 2006;Fouquet et al 2016). Loose descriptions also prevent the correct evaluation of conservation recommendations because identification problems affect the accuracy of the species distribution.…”