Abstract
Reserva Las Gralarias is one of the best-studied localities of the Ecuadorian Andes in terms of its batrachofauna. However, as expected in any community, some species are rare and, therefore, their discovery and description are problematic. Herein, based on a single specimen, we describe Pristimantis gralarias sp nov. Even though we are aware of the problems associated to singleton species (i.e., unknown intraspecific variation, limited ecological information), our efforts to finding additional specimens have been unsuccessful. Thus, given the importance of species descriptions in threatened areas (e.g. Andes), and that the new taxon is supported by both morphological and genetic data, we consider that the description is justified. Pristimantis gralarias sp nov is easily distinguished from all other members of the P. myersi group by its long and slender fingers and toes, with discs that are not expanded laterally (or are only slightly expanded). Furthermore, the new species is characterized by having a black venter with minute white spots and a red groin. A molecular phylogeny corroborates the placement of the new species in the P. myersi group and its distinctiveness in relation to other species. Finally, we discuss on the limitations and advantages associated to species descriptions based on one or few specimens.
References
AmphibiaWeb (2018) AmphibiaWeb: Information on amphibian biology and conservation. Available from: http://amphibiaweb.org (accessed 13 November 2018)
Arteaga, A., Bustamante, L. & Guayasamin, J.M. (2013) Amphibians and Reptiles of Mindo: Life in the Coudforest. 1st Edition. Universidad Tecnológica Indoamérica, Quito, 258 pp.
Castroviejo-Fisher, S., Vilà, C., Ayarzagüena, J., Blanc, M. & Ernst, R. (2011) Species diversity of Hyalinobatrachium glassfrogs (Amphibia: Centrolenidae) from the Guiana Shield, with the description of two new species. Zootaxa, 3132, 1–55.
Centro Jambatu (2011–2017) Anfibios de Ecuador. Available from: http://www.anfibiosecuador.ec/index.php?aw,2 (accessed 13 November 2018)
de Queiroz, K. (2007) Species concepts and species delimitation. Systematic Biology, 56, 879–886.
https://doi.org/10.1080/10635150701701083
Coloma, L.A., Carvajal-Endara, S., Dueñas, J.F., Paredes-Recalde, A., Morales-Mite, M., Almeida-Reinoso, D., Tapia, E.E., Hutter, C.R., Toral, E. & Guayasamin, J.M. (2012) Molecular phylogenetics of stream treefrogs of the Hyloscirtus larinopygion group (Anura: Hylidae), and description of two new species from Ecuador. Zootaxa, 3364, 1–78.
Duellman, W.E. & Burrowes, P.A. (1989) New species of frogs, Centrolenella, from the Pacific versant of Ecuador and southern Colombia. Occasional Papers of the Museum of Natural History, University of Kansas, 132, 1–14.
Frost, D. (2018) Amphibian Species of the World: an Online Reference. Version 6.0. Available from: http://research.amnh.org/herpetology/amphibia/index.html (accessed 13 November 2018)
González-Durán, G.A., Targino, M., Rada, M. & Grant, T. (2017) Phylogenetic relationships and morphology of the Pristimantis leptolophus species group (Amphibia: Anura: Brachycephaloidea), with the recognition of a new species group in Pristimantis Jiménez de la Espada, 1870. Zootaxa, 4243 (1), 42–47.
https://doi.org/10.11646/zootaxa.4243.1.2
Guayasamin, J.M. (2004) A new species of Eleutherodactylus (Anura: Leptodactylidae) from the lowlands of northwestern Ecuador. Herpetologica, 60, 103–116.
https://doi.org/10.1655/02-106
Guayasamin, J.M. & Funk, C.W. (2009) The amphibian community at Yanayacu Biological Station, Ecuador, with a comparison of vertical microhabitat use among Pristimantis species and the description of a new species of the Pristimantis myersi group. Zootaxa, 2220, 41–66.
Guayasamin, J.M., Mendoza, A.M., Longo, A.V., Zamudio, Z. & Bonaccorso, E. (2014) High prevalence of Batrachochytrium dendrobatidis in an Andean frog community (Reserva Las Gralarias, Ecuador). Amphibian & Reptile Conservation, 8, 33–44.
Guayasamin, J.M., Krynak, T., Krynak, K., Culebras, J. & Hutter, C.R. (2015) Phenotypic plasticity raises questions for taxonomically important traits: a remarkable new Andean rainfrog (Pristimantis) with the ability to change skin texture. Zoological Journal of the Linnean Society, 173, 913–928.
https://doi.org/10.1111/zoj.12222
Guayasamin, J.M., Hutter, C.R., Tapia, E.E., Culebras, J., Peñafiel, N., Pyron, R.A., Morochz, C., Funk, C. & Arteaga, A. (2017) Diversification of the rainfrog Pristimantis ornatissimus in the lowlands and Andean foothills of Ecuador. PLOS One, 12, e0172615.
https://doi.org/10.1371/journal.pone.0172615
Heinicke, M.P., Duellman, W.E. & Hedges, S.B. (2007) Major Caribbean and Central American frog faunas originated by ancient oceanic dispersal. PNAS, 104, 10092–97.
https://doi.org/10.1073/pnas.0611051104
Hutter, C.R. & Guayasamin, J.M. (2012) A new cryptic species of glassfrog (Centrolenidae: Nymphargus) from Reserva Las Gralarias, Ecuador. Zootaxa, 3257, 1–21.
Hutter, C.R. & Guayasamin, J.M. (2015) Cryptic diversity concealed in the Andean cloud forests: two new species of rainfrogs (Pristimantis) uncovered by molecular and bioacoustic data. Neotropical Biodiversity, 1, 36–59.
https://doi.org/10.1080/23766808.2015.1100376
Hutter, C.R., Lambert, S.M. & Wiens, J.J. (2017) Rapid diversification and time explain amphibian species richness at different scales in the Tropical Andes, Earth’s most biodiverse hotspot. The American Naturalist, 19, 828–843.
https://doi.org/10.1086/694319
IUCN (2001) IUCN Red List Categories and Criteria. Version 3.1. IUCN Species Survival Commission. IUCN, Gland and Cambridge.
Jiménez de la Espada, M. (1870) Fauna neotropicalis species quaedam nondum cognitae. Jornal de Sciências, Mathemáticas, Physicas e Naturaes, Lisboa, 3, 57–65.
Lim, G.S., Balke, M. & Meier, R. (2012) Determining species boundaries in a world full of rarity: singletons, species delimitation methods. Systematic Biology, 61, 165–169.
https://doi.org/10.1093/sysbio/syr030
Lynch, J.D. (1976) Three new leptodactylid frogs (genus Eleutherodactylus) from the Andean slopes of Colombia and Ecuador. Herpetologica, 32, 310–317.
Lynch, J.D. (1981) Leptodactylid frogs of the genus Eleutherodactylus in the Andes of Northern Ecuador and adjacent Colombia. Miscellaneous Publications of the Museum of Natural History, University of Kansas, 72, 1–46.
https://doi.org/10.5962/bhl.title.16289
Lynch, J.D. & Duellman, W.E. (1997) Frogs of the genus Eleutherodactylus in western Ecuador: Systematics, ecology, and biogeography. Special Publications of the Museum of Natural History, University of Kansas, 23, 1–236.
Lynch, J.D. & Burrowes, P.A (1990) Frogs of the genus Eleutherodactylus at the La Planada Reserve in southwestern Colombia (family Leptodactylidae). Occasional Papers of the Museum of Natural History, University of Kansas, 136, 1–31.
Köhler, J. & Padial, J.M. (2016) Description and phylogenetic position of a new (singleton) species of Oreobates Jiménez de la Espada, 1872 (Anura: Craugastoridae) from the Yungas of Cochabamba, Bolivia. Annals of Carnegie Museum, 84, 23–38.
https://doi.org/10.2992/007.084.0104
Magurran, A.E. & Henderson, P.A. (2003) Explaining the excess of rare species in natural species abundance distributions. Nature, 422, 714–716.
https://doi.org/10.1038/nature01547
Padial, J.M., Grant, T. & Frost, D.R. (2014) Molecular systematics of terraranas (Anura: Brachycephaloidea) with an assessment of the effects of alignment and optimality criteria. Zootaxa, 3825 (1), 1–132.
https://doi.org/10.11646/zootaxa.3825.1.1
Palacios-González, M., Bonaccorso, E. & Papeş, M. (2015) Applications of geographic information systems and remote sensing techniques to conservation of amphibians in northwestern Ecuador. Global Ecology and Conservation, 3, 562–574.
https://doi.org/10.1016/j.gecco.2015.02.006
Rivera-Correa, M., Jimenez, C. & Daza, J.M. (2017) Phylogenetic analysis of the Neotropical Pristimantis leptolophus species group (Anura: Craugastoridae): molecular approach and description of a new polymorphic species. Zootaxa, 4242 (2), 313–343.
https://doi.org/10.11646/zootaxa.4242.2.6
Rojas-Runjaic, F.J.M. (2012) Species limits in direct-developing frogs of the Pristimantis myersi species group (Terrarana: Strabomantidae). Master Thesis, Universidad Internacional Menéndez Pelayo, Consejo Superior de Investigaciones Científicas, Spain.
Rojas-Runjaic, F.J.M., Delgado-C., A.J. & Guayasamin, J.M. (2014) A new rainfrog of the Pristimantis myersi Group (Amphibia, Craugastoridae) from Volcán Pichincha, Ecuador. Zootaxa, 3780 (1), 36–50.
https://doi.org/10.11646/zootaxa.3780.1.2
Rödder, D. & Schmitz, A. (2009) Two new Pristimantis (Anura, Strabomantidae) belonging to the myersi group from the Andean slopes of Ecuador. Revue Suisse de Zoologie, 116, 275–288.
https://doi.org/10.5962/bhl.part.79496
Sánchez-Nivicela, J.C., Celi-Piedra, E., Posse-Sarmiento, V., Urgilés, V.L., Yánez-Muñoz, M. & Cisneros-Heredia, D.F. (2018) A new species of Pristimantis (Anura, Craugastoridae) from the Cajas Massif, southern Ecuador. ZooKeys, 751, 113–128.
https://doi.org/10.3897/zookeys.751.20541
Valencia, J., Dueñas, M.R., Székely, P., Batallas, D., Pulluquitín, F. & Ron, S.R. (2017) A new species of direct-developing frog of the genus Pristimantis (Anura: Terrarana: Craugastoridae) from Cordillera del Cóndor, Ecuador, with comments on threats to the anuran fauna of the region. Zootaxa, 4353 (3), 447–466.
https://doi.org/10.11646/zootaxa.4353.3.3
Yánez-Muñoz, M.H., Meza-Ramos, P., Cisneros-Heredia, D.F. & Reyes-Puig, J.P. (2011) "2010" Descripción de tres nuevas especies de ranas del género Pristimantis (Anura: Terrarana: Strabomantidae) de los bosques nublados del Distrito Metropolitano de Quito, Ecuador. Avances en Ciencias e Ingeníerias, Sección B, 2, B16–B27.
Zhang, P., Liang, D., Mao, R.L., Hillis, D.M., Wake, D.B. & Canatella, D.C. (2013) Efficient sequencing of anuran mtDNAs and a mitogenomic exploration of the phylogeny and evolution of frogs. Molecular Biology and Evolution, 30, 1899–915.
https://doi.org/10.1093/molbev/mst091