Friday, May 1, 2015

[Herpetology • 2015] Five New Species of Pristimantis (Anura: Strabomantidae) from the Coastal Cloud Forest of the Península de Paria, Venezuela


Image 3. Pristimantis nubisilva sp. nov. from the Península de Paria in northeastern Venezuela.
(C) Calling male from the Las Melenas area (specimen not collected). (D) Individual from Cerro Humo, showing the red dorsal tuberculation present in some frogs (specimen not collected).
Image 8. Specimens of Pristimantis hoogmoedi sp. nov. from the Península de Paria in northeastern Venezuela, photographed in life.
(A) Male paratype (CVULA 7440, SVL = 34.3mm), illustrating the relatively plain dorsal patterning with irregular brown markings and the red iris. (B) Female paratype (CVULA 7434, SVL = 41.6mm), illustrating the ‘extravagant’ orange-brown patterned phenotype.
Image 12. Pristimantis geminus sp. nov. from the Península de Paria in northeastern Venezuela in life.
 (A) Male holotype (USNM [CMD 341], SVL = 20.8mm), illustrating paired scapular spots and associated tubercles. (C) Male and female P. geminus from Cerro Patao in axillary amplexus (MBLUZ 381–82). The male illustrates the dark brown striped phenotype, showing scapular tubercles and the conical tubercle on the upper eyelid. In these individuals, the coloration is particularly vibrant, perhaps owing to the reproductive activity.

Abstract

 Fieldwork in the cloud forest of Venezuela’s remote Península de Paria in 2001 resulted in the collection of several specimens that could unquestionably be classified as members of the genus Pristimantis. Subsequent analysis of comparative material in museum collections brought the total number of specimens to 44, and these collectively represent five new species. Two of these species, P. geminus sp. nov. and P. nubisilva sp. nov., have phenotypes remarkably similar to the Trinidadian P. urichi, supporting a prediction that Pristimantis from easternmost Venezuela may have given rise to Trinidadian forms. Pristimantis hoogmoedi sp. nov. is easily identified by its large size and red eyes. Two of the species, P. longicorpus sp. nov. and P. pariagnomus sp. nov., are very distinct morphologically but are known only from the holotypes. The former is characterized by an elongate body form supported by relatively short limbs, whereas the latter has very distinctive hand morphology and is likely the smallest Venezuelan frog. Chromosome banding studies of P. nubisilva sp. nov. and P. hoogmoedi sp. nov. revealed chromosome numbers of 2n = 36 and 2n = 26, respectively, with an unusual submetacentric fusion chromosome 11;18 in some males of the former and a unique meiotic pairing of chromosomes in males of the latter. All five species can be readily distinguished by their osteology, such as by the extent of the sphenethmoid and features on the roof of the mouth, as well as by the shape and rearrangement of mesopodial elements. The unexpectedly high diversity of Pristimantis in this region, along with high endemism of amphibians and reptiles in general, underscores the position of the Península de Paria as a center for frog biodiversity in Venezuela. The similarity of these Paria species to Pristimantis from Trinidad, Tobago and the central Cordillera de la Costa represents a tangible piece of evidence for the close biogeographic link of the anuran fauna of these landmasses.

Keywords: Biogeography, chromosomes, new species, osteology, Península de Paria, Pristimantis, taxonomy, Trinidad, Tobago, Venezuela

Image 17. Uncollected specimen of Pristimantis pariagnomus sp. nov. from Cerro Humo on the Península de Paria in northeastern Venezuela. Based on several characteristics, this individual can unequivocally be referred to the new species, particularly by the morphology of its fingers. © Mayke De Freitas
Image 18. Male holotype (MHNLS 14456, SVL = 13.0mm) of Pristimantis pariagnomus sp. nov. in dorsal (A) and ventral (B) views.


  Kaiser, H., C.L. Barrio-Amorós, G.A. Rivas, C. Steinlein & M. Schmid. 2015. Five New Species of Pristimantis (Anura: Strabomantidae) from the coastal cloud forest of the Península de Paria, Venezuela. Journal of Threatened Taxa. 7(4): 7047–7088. DOI: 10.11609/JoTT.o4197.7047-88

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