Wednesday, December 27, 2023

[Herpetology • 2023] Pristimantis similaris • A New Cryptic Species of Terrestrial Breeding frog of the Pristimantis danae Group (Anura: Strabomantidae) from montane forests in Ayacucho, Peru


Pristimantis similaris 
Herrera-Alva, Catenazzi & Aguilar-Puntriano, 2023

Photos by V. Diaz-Vargas and E. Castillo-Urbina.

Abstract
Based on morphological and molecular characters, we describe a new species of terrestrial breeding frog of the Pristimantis danae Group from montane forests of La Mar Province, Ayacucho Department in southern Peru, at elevations from 1200 to 2000 m a.s.l. The phylogenetic analysis, based on concatenated sequences of gene fragments of 16S rRNA, RAG1, COI and TYR suggests that the new species is a sister taxon of a clade that includes one undescribed species of Pristimantis from Cusco, Pristimantis pharangobates and Pristimantis rhabdolaemus. The new species is most similar to P. rhabdolaemus, which differs by lacking scapular tubercules and by its smaller size (17.0–18.6 mm in males [n = 5], 20.8–25.2 mm in females [n = 5] in the new species vs. 22.8–26.3 mm in males [n = 19], 26.0–31.9 mm in females [n = 30] of P. rhabdolaemus). Additionally, we report the prevalence of Batrachochytrium dendrobatidis (Bd) in this species.

Key words: Chytridiomycosis, cryptic species, montane forests, morphology, phylogeny

Pristimantis similaris sp. nov. (A–D) male. SVL: 17.0 mm. Holotype. MUSM 41030.
Photos by Vladimir Diaz-Vargas.

A–H colour and pattern variation of Pristimantis similaris sp. nov. 
 Specimen from A–F collected in Cajadela:
A, B male MUSM 41029 C, D female MUSM 41031
E, F female MUSM 41032. Specimen G, H male MUSM 41326 collected in Machente.
Photos by V. Diaz-Vargas and E. Castillo-Urbina.

 Pristimantis similaris sp. nov.
 
Common name: English: Similar Rubber Frog.
 Spanish: Rana cutín similar.

Diagnosis: A new species of Pristimantis assigned to the P. danae species Group having the following combination of characters: (1) Skin on dorsum shagreen, skin on venter areolate; discoidal and dorsolateral folds present, weak; thoracic fold present; (2) tympanic membrane and tympanic annulus present, distinct, visible externally; (3) snout subaccuminated in dorsal view, round in lateral view; (4) upper eyelid lacking tubercles; EW smaller than IOD; cranial crest absent; two small and flat tubercles above the snout near the eyes; (5) dentigerous processes of vomers low, oblique in five of the paratypes, absent in four paratypes and the holotype; (6) males with vocal slits, subgular vocal sac large extending on to chest and without nuptial pads; (7) Finger I slightly shorter than Finger II; discs of digits expanded, flat and truncated; (8) fingers without lateral fringes; (9) ulnar tubercles present, but diffuse; (10) heel with two to three small and flat tubercles; inner tarsal fold present, small; (11) inner metatarsal tubercle ovoid, 2–3 times larger ...

Etymology: The specific name corresponds to the Latin word “similar”. This refers to the similarity of the new species and its close phylogenetic relationship with P. rhabdolaemus and P. pharangobates.


 Valia Herrera-Alva, Alessandro Catenazzi and César Aguilar-Puntriano. 2023. A New Cryptic Species of Terrestrial Breeding frog of the Pristimantis danae Group (Anura, Strabomantidae) from montane forests in Ayacucho, Peru. ZooKeys. 1187: 1-29.  DOI: 10.3897/zookeys.1187.104536

Resumen: Describimos una nueva especie de rana terrestre de desarrollo directo del grupo Pristimantis danae de bosques montanos procedentes de la provincia de La Mar, departamento de Ayacucho al sur de Perú con rango de distribución altitudinal entre los 1200–2000 msnm, en base a caracteres morfológicos y moleculares. El análisis filogenético basado en las secuencias concatenadas de los fragmentos de genes ARNr 16S, COI, RAG1 y TYR sugiere que la nueva especie es un taxón hermano del clado que incluye a una especie de Pristimantis no descrita de Cusco, Pristimantis pharangobates y Pristimantis rhabdolaemus. La nueva especie se asemeja más a P. rhabdolaemus; de la cual difiere por la ausencia de tubérculos escapulares y su menor tamaño corporal (17.0–18.6 mm en machos [n=5], 20.8–25.2 mm en hembras [n=5] en la nueva especie vs 22.8–26.3 mm en machos [n=19], 26.0–31.9 mm en hembras [n=30] de P. rhabdolaemus). Adicionalmente, reportamos la prevalencia de Batrachochytrium dendrobatidis (Bd) en esta especie de Terrarana.
Palabras clave: Bosques montanos, especies crípticas, filogenia, morfología, quitridiomicosis