Fifty years after: A taxonomic revision of the amphibian species from the Ecuadorian biodiversity hotspot Abra de Zamora, with description of two new Pristimantis species

lack of discoidal and thoracic folds in the specimen collected from Cajanuma. Duellman and Lehr [25] list the discoidal fold as absent, but Motta et al. [27] consider that discoidal and tho- racic folds are present. Specimen MUTPL 342 lacked both folds (in life as well as in preserva- tive; Fig 4B). On the other hand, all the specimens collected by us nearby Saraguro and San Lucas have evident discoidal and thoracic folds, so it might be possible that this feature is char- acteristic for the individuals of this currently undescribed species. Similarly, we observed the skin on dorsum as shagreen, with a more granular texture on the back and dorsal surfaces of hindlimbs, but without tubercles (Fig 4A), and thus, in accordance to Duellman and Lehr [25], we did not observed any tubercles on the upper eyelids, either in life or in preservative (Fig 4C). Genus Pristimantis Jime´nez de la Espada, 1870 Pristimantis orestes species group [sensu 6, 16, 48]. Three species of this species group were described from Abra de Zamora. We add our description of an additional two new spe- cies further below. Phylogeny For the Pristimantis orestes species group, PartitionFinder under AICc (for ML) identified four partition schemes as the best strategy (best model in parentheses): 12S (GTR+I+G), 16S (GTR+I+G), RAG-1 1st and 2nd positions (F81+G), and RAG-1 3rd position (TVM+G). Under BIC (for BI) PartitionFinder identified three partitions: 12S and 16S (GTR+I+G), RAG-1 1st and 2nd positions (F81+G), and RAG-1 3rd position (K80+G). The phylogenetic trees con-

structed by Bayesian inference and Maximum likelihood showed exactly the same topology, but with overall stronger support in the case of the Bayesian inference (Fig 7). Once again, we recovered the P. orestes species group as monophyletic, with strong support (bootstrap values = 100%; posterior probabilities = 1) in both ML and Bayesian analyses (Fig 7). Our analysis confirmed the membership of P. vidua, P. colodactylus and two new species, i.e. P. samaniegoi sp. nov. and P. matildae sp. nov., to the P. orestes species group. In general, the phylogenetic tree in our analysis showed the same topology with the one constructed by Urgilles et al. [16], but the addition of the new species to the group changed the kinship between some of the species. Also, differences appeared in the position of some unresolved branches such as P. tiktik or P. saturninoi (Fig 7). Our phylogenetic tree reveals three, strongly supported, large subgroups of species: the P. orestes subgroup (with P. andinognomus, P. orestes, P. vidua, an undescribed species and P. cajanuma), the closely related P. simonbolivari subgroup (with P. tiktik, P. saturninoi, P. simon- bolivari, P. bambu, P. mazar, P. quintanai, P. samaniegoi sp. nov and two undescribed species) and the morphologically distinct, bromeliad specialist, P. colodactylus subgroup (with P. matil- dae sp. nov., P. colodactylus, P. muranunka and an undescribed species). Pristimantis andinognomus Lehr and Coloma, 2008 Common English name. Andean Dwarf Robber Frog Common Spanish name. Cutı´n nomo

Etymology. The specific name is derived from the New Latin noun Andinus meaning “Andes” and the New Latin noun gnomus meaning “dwarf” and refers to the small size of the species, which at the time of description was the smallest species of the genus [13]. Holotype. QCAZ 16695, an adult male, from Reserva Tapichalaca, on the road between Yangana and Valladolid (2667 m), Provincia Zamora-Chinchipe, Ecuador, collected by Italo G. Tapia and Queti M. Tapia on 17 September 2001. Paratypes. 20 males: QCAZ 16669, 16672–74, 16685–88, 16690–93, 26326, 26329, 26331, 26343, 26347, 26352, 26964–65, 19 females: QCAZ 16670–71, 16675–78, 16680–84, 16689, PLOS ONE Taxonomic revision of the amphibian species from Abra de Zamora PLOS ONE | https://doi.org/10.1371/journal.pone.0238306 September 10, 2020 14 / 59