Lourdes Y. Echevarría

We describe two new species of Stenocercus from the eastern and western slopes of Cordillera Blanca and Cordillera Negra, respectively, in central Peru. Both lineages were previously identified through phylogenetic and species delimitation analyses, in a recent integrative study of S. chrysopygus populations. Both new species share granular scales on the posterior surface of thighs, antehumeral and oblique neck folds, and lack of a vertebral crest with similar Stenocercus species. Stenocercus albociliaris sp. nov. can be differentiated from these congeners by having the dorsal surface of head and neck black with numerous and scattered cream dots, and a cream stripe over canthals and superciliaries in adult males. Stenocercus conchucos sp. nov. can also be distinguished from them, except S. aguilari, by having a blue venter with a black hourglass shaped patch continuous to chest and thighs, pelvic region, and shanks in adult males. S. conchucos differs from S. aguilari, by the presence of cream dorsolateral stripes in adult males, a brown dorsal coloration with cream and black markings, and fewer scales around midbody. Finally, we provide an updated diagnosis for S. chrysopygus, along with information on its variation and natural history, contributing to the taxonomic knowledge of this recently revised species. Describimos dos nuevas especies de Stenocercus provenientes de las vertientes oriental y occidental de la Cordillera Blanca y la Cordillera Negra, respectivamente, en el centro del Perú. Ambos linajes fueron identificados previamente mediante análisis filogenéticos y de delimitación de especies en un estudio integrativo reciente de las poblaciones de S. chrysopygus. Ambas especies nuevas comparten con otras especies afines de Stenocercus la presencia de escamas granulares en la superficie posterior de los muslos, pliegues antehumerales y nucales oblicuos, y la ausencia de cresta vertebral. Stenocercus albociliaris sp. nov. se diferencia de estas especies congéneres por presentar la superficie dorsal de la cabeza y el cuello de color negro con numerosos puntos de color crema dispersos, así como una franja crema sobre las escamas cantales y supraciliares en los machos adultos. Stenocercus conchucos sp. nov. también se distingue de ellas, excepto S. aguilari, por presentar, en los machos adultos, una región ventral azul con una mancha negra en forma de reloj de arena que se extiende hacia el pecho, los muslos, la región pélvica y las pantorrillas. S. conchucos difiere de S. aguilari por la presencia de franjas dorsolaterales crema en los machos adultos, una coloración dorsal parda con marcas crema y negras, y un menor número de escamas alrededor de la mitad del cuerpo. Finalmente, presentamos una diagnosis actualizada de S. chrysopygus, junto con información sobre su variación e historia natural, contribuyendo así al conocimiento taxonómico de esta especie recientemente revisada.

Nearly two decades ago, the gymnophthalmid lizard Petracola ventrimaculata was hypothesized to be a species complex based on dorsal and ventral color pattern differences among populations within a wide and disjunct geographical area in the northern Peruvian Andes. Here, we address this proposal using both molecular and morphological evidence. We analyzed a molecular matrix of Cercosaurinae, including 22 specimens and 78 DNA sequences of P. ventrimaculata sensu lato to study the phylogenetic relationships among its populations. We also conducted a detailed examination of the external morphology of 236 P. ventrimaculata specimens from several populations. Based on our analyses, we describe five new Petracola species, two of them previously assigned to P. ventrimaculata, from Cordillera Occidental and Cordillera Central in northern Peru. P. ventrimaculata sensu stricto is distributed across several localities in Cajamarca department in the northern part of the Cordillera Occidental in northwestern Peru. We hypothesize that the distribution patterns within the Petracola ventrimaculata species complex could be related to vicariant processes driven by the complex orogeny of the Huancabamba Depression and the Marañón River valley. Given its distinctive morphological traits and disjunct distribution, we recommend treating P. labioocularis as incertae sedis within Cercosaurinae, pending molecular data to resolve its phylogenetic placement. We present recommendations for future descriptions of new species of Petracola.

We describe Gastrotheca mittaliiti sp. nov. from the subalpine paramo of Amazonas department in the Andes of northern Peru, in the Huancabamba region, based on phylogenetic analysis of DNA sequences from three mitochondrial and two nuclear genes, genetic distances, and diagnostic morphological characters. Our phylogenetic analysis recovered the new species with high support both as part of the Gastrotheca marsupiata species group and as the sister species of G. trachyplevra. The new species can be distinguished from the rest of its congeners by the combination of the following characters: (i) moderately small size in males (SVL = 27.6–32.5 mm, n = 4); (ii) distinctly thick and elevated supratympanic fold extending from the top edge of the tympanum to the flank covered with prominent and closely packed or fused pustules; (iii) two prominent paravertebral longitudinal pustular ridges; (iv) narrow discs on fingers and toes with truncate terminal margins; (v) dorsum covered with prominent and closely packed rounded pustules; (vi) canthus rostralis thin and straight in dorsal view; and (vii) distal subarticular tubercle rounded. In addition, we report the first record of G. turnerorum in Peru and describe new morphological variation of the Peruvian populations. Our results highlight the Huancabamba region as the hotspot of Gastrotheca species richness, a result that we discuss from a biogeographic and conservation perspective.

The assessment of the taxonomic status of Stenocercus chrysopygus Boulenger, 1900, a conspicuous species inhabiting the upper valleys of the Santa, Chiquián, and Marañón rivers in central Peru, has been pending for decades. We studied the phylogenetic relationships and variation of several populations using mitogenomes, DNA barcode datasets, and morphological evidence. We present a phylogeny of Stenocercus combining available mitochondrial sequences with 37 mitochondrial genes from S. chrysopygus and closely related congeners samples. Our results support S. chrysopygus as a species complex, with three additional species among the studied populations. Populations from the Santa River valley, including all syntype localities, correspond to S. chrysopygus sensu stricto.

We describe a new species of Selvasaura from the montane forests of the eastern slopes of the Andes in northern Peru, based on external and hemipenial morphological characters and previous phylogenetic analyses. The new species can be differentiated from the other two Selvasaura species in having keeled dorsal scales usually flanked by longitudinal striations, in adults and juveniles; adult males with a yellow vertebral stripe bordered by broad dark brown stripes on each side and a unilobed hemipenis surrounded by the branches of the sulcus spermaticus. The description of the new species contributes information about new states of diagnostic characters of Selvasaura and natural history.

We study the phylogenetic relationships of egg‐brooding frogs, a group of 118 neotropical species, unique among anurans by having embryos with large bell‐shaped gills and females carrying their eggs on the dorsum, exposed or inside a pouch. We assembled a total evidence dataset of published and newly generated data containing 51 phenotypic characters and DNA sequences of 20 loci for 143 hemiphractids and 127 outgroup terminals. We performed six analytical strategies combining different optimality criteria (parsimony and maximum likelihood), alignment methods (tree‐ and similarity‐alignment), and three different indel coding schemes (fifth character state, unknown nucleotide, and presence/absence characters matrix). Furthermore, we analyzed a subset of the total evidence dataset to evaluate the impact of phenotypic characters on hemiphractid phylogenetic relationships. Our main results include: (i) monophyly of Hemiphractidae and its six genera for all our analyses, novel relationships among hemiphractid genera, and non‐monophyly of Hemiphractinae according to our preferred phylogenetic hypothesis; (ii) non‐monophyly of current supraspecific taxonomies of Gastrotheca, an updated taxonomy is provided; (iii) previous differences among studies were mainly caused by differences in analytical factors, not by differences in character/taxon sampling; (iv) optimality criteria, alignment method, and indel coding caused differences among optimal topologies, in that order of degree; (v) in most cases, parsimony analyses are more sensitive to the addition of phenotypic data than maximum likelihood analyses; (vi) adding phenotypic data resulted in an increase of shared clades for most analyses.

We describe two new sympatric species of Stenocercus from the seasonally dry forest of the inter-Andean valley of the Mantaro River (Huancavelica department) in the Central Andes of central-southern Peru, at elevations of 1,693 to 2,920 m asl. Stenocercus diploauris sp. nov. is similar to S. formosus and S. ochoai, but differs in having a longitudinal neck fold and C-shaped nuchal mite pocket around the oblique fold and posteriorly limited by the antehumeral fold. Stenocercus nigrobarbatus sp. nov. is similar to S. frittsi and S. variabilis, however it can be distinguished by having a postfemoral mite pocket with one or more vertical folds or ridges and by the presence, in adult males, of a continuous black patch covering the infralabials, throat, chest, ventral surfaces of forelimbs, belly (as a midventral line), ventral surfaces of hind limbs, and pelvic region.

Pristimantis lassoalcalai Barrio-Amorós, Rojas-Runjaic & Barros, 2010 is a poorly known terrarana, endemic to the eastern slope of Sierra de Perijá in Venezuela. Although a close relationship of this species with Tachiramantis has been suspected based on its overall morphological similarity, this relationship had not been tested so far. On the basis of molecular data (two fragments of the 12S and 16S mtDNA genes) obtained from the type series, we reconstruct its evolutionary relationships and establish its phylogenetic position as a member of Tachiramantis. Based on this phylogenetic hypothesis, we transfer Pristimantis lassoalcalai to Tachiramantis as Tachiramantis lassoalcalai comb. nov. In addition, we describe its advertisement call. This is the fourth known species of the genus and the second to which its vocalization is described.

Morphology and distribution of the South American snake Chironius leucometapus (Serpentes: Colubridae). Chironius leucometapus was described more than 25 years ago as subspecies of C. fuscus from restricted area in the Department of Junín in central Peru, with no additional specimens reported since. Examination of 17 new specimens reveals that C. leucometapus is widespread along the Amazonian slopes of the Andes between central Peru and northern Ecuador. New morphological data including scalation, hemipenes, color in life, and the frst description of the skull of Chironius to be based on high-quality CT-scan images are presented. The number of species of Chironius from Ecuador is elevated to eight.