[Herpetology • 2020] Riolama grandis & R. stellata • Lizards from the Lost World: Two New Species and Evolutionary Relationships of the Pantepui Highland Riolama (Gymnophthalmidae)

Riolama stellata & R. grandis

Recoder, Prates, Marques-Souza, Camacho, Nunes, Vechio, Ghellere, McDiarmid & Rodrigues, 2020

DOI: 10.1093/zoolinnean/zlz168 

IvanPrates.org/publications 

Abstract
The Pantepui region of northern South America harbours an endemic fauna that differs dramatically from those of the surrounding lowland rainforests and savannas. A component of this unique fauna is Riolama, a poorly known genus of microteiid lizards with four described and two undescribed species restricted to tepui mountains. We here implement an integrative approach to formally describe the two unnamed species and investigate the phylogenetic relationships and timing of diversification in Riolama using a fossil-calibrated molecular approach. Our results suggest that diversification initiated in Riolama during the Oligocene (c. 28 Mya), thereby characterizing the genus as an ancient lineage. This supports the Plateau biogeographic hypothesis to explain the diversification of the Pantepui fauna. Our divergence time estimation analysis also provides an updated temporal framework for the diversification of the highly diverse Gymnophthalmidae clade.

Keywords: diversity, endemism, herpetofauna, MRCA, taxonomy, tepui

 Riolama grandis in life.
 paratype (MZUSP 116629, field number MTR 40266), a juvenile male with 41.0 mm SVL.

Riolama grandis Recoder et al., sp. nov.

Riolama sp. nov. a, McDiarmid et al., 1988: 669. 

Riolama sp. A (Neblina), McDiarmid & Donnelly, 2005: 515, 540; Kok, 2015: 501, fig. 7.
"The Brown Giant"

Etymology: The specific epithet, grandis, is a Latin adjective, meaning ‘big’ or ‘large’, in reference to the larger body size of this new species compared to congeners

Paratopotype of Riolama stellata in life (MZUSP 116617, field number MTR 40309), an adult male with 41.9 mm SVL.  

Riolama stellata Recoder et al., sp. nov.

Riolama sp. nov. b, McDiarmid et al., 1988: 669. 

Riolama sp. B (Neblina), McDiarmid & Donnelly, 2005: 515, 540; Kok, 2015: 501, fig. 7.
"The Night Sky" 

Etymology: The specific epithet is the Latin adjective stellatus, which means ‘starred’, referring to the ventral and lateral colour pattern composed of light dots scattered on a dark background, which resemble a starry night sky.


Renato Recoder, Ivan Prates, Sergio Marques-Souza, Agustín Camacho, Pedro M. Sales Nunes, Francisco Dal Vechio, José Mario Ghellere, Roy W. McDiarmid and Miguel Trefaut Rodrigues. 2020. Lizards from the Lost World: Two New Species and Evolutionary Relationships of the Pantepui Highland Riolama (Gymnophthalmidae). Zoological Journal of the Linnean Society. zlz168. DOI:  10.1093/zoolinnean/zlz168 

  IvanPrates.org/publications

Lagartos da Neblina: cientistas descrevem novas espécies do ponto mais alto do Brasil 

  jornal.usp.br/ciencias/ciencias-biologicas/lagartos-da-neblina-cientistas-descrevem-novas-especies-do-ponto-mais-alto-do-brasil/

Novos lagartos do pico da Neblina

  revistapesquisa.fapesp.br/2020/02/12/novos-lagartos-do-pico-da-neblina/

[Herpetology • 2020] Allobates pacaas • A New Nurse frog from Southwestern Amazonian Highlands, with Notes on the Phylogenetic Affinities of Allobates alessandroi (Aromobatidae)

Allobates pacaas 

Melo-Sampaio, Prates, Peloso, Recoder, Dal Vechio, et al., 2020. 

DOI: 10.1080/00222933.2020.1727972 

IvanPrates.org/publications
  twitter.com/I_Prates

ABSTRACT

Few studies have focused on the diverse fauna of southwestern Brazilian Amazonia. This region, spared from large-scale human occupation until the second half of the twentieth century, has been threatened by expanding agriculture, logging, and mining. Here, we describe a new nurse frog (Allobates, Aromobatidae) from the open highland habitats of Serra dos Pacaás Novos, one of the few large remnants of relatively intact native vegetation in the Brazilian state of Rondônia. The new species is diagnosed by its metallic orange dorsal colouration, weakly expanded discs on hands, and presence of two subarticular tubercles on Finger IV. A phylogenetic analysis based on DNA sequence data recovered the new species as more closely related to nurse frogs from the Madeira and Tapajós River basins; this pattern may reflect a history of dispersal uphill from a lowland ancestor. Our results also indicate that the generic assignment of Allobates alessandroi (Grant and Rodriguez, 2001), a high-elevation species from the Andes of Peru, needs to be reassessed; we discuss the phylogenetic affinities of this species based on morphological attributes.

KEYWORDS: Amazon, amphibia, phylogeny, taxonomy, Allobates pacaas sp. nov.

Figure 4. Dorsal (a) and ventral (c) views of the female holotype of Allobates pacaas sp. nov. (MZUSP 158934) in life. Dorsal (b) and ventral (d) views of male paratype MZUSP 158938 in life.

Allobates pacaas sp. nov.

Etymology. Allobates pacaas is named in recognition of an important natural refuge in the Brazilian state of Rondônia. The region has experienced intense deforestation since the 1960s with large-scale loss of biodiversity (Fearnside 1987). The specific epithet is a noun in apposition to the genus.

Habitat where Allobates pacaas was found in the Serra dos Pacaás National Park.

Paulo R. Melo-Sampaio, Ivan Prates, Pedro L. V. Peloso, Renato Recoder, Francisco Dal Vechio, Sergio Marques-Souza and Miguel T. Rodrigues. 2020. A New Nurse frog from Southwestern Amazonian Highlands, with Notes on the Phylogenetic Affinities of Allobates alessandroi (Aromobatidae). Journal of Natural History. [Amphibian Taxonomy: Early 21st Century Case Studies] DOI: 10.1080/00222933.2020.1727972

IvanPrates.org/publications

 twitter.com/I_Prates/status/1234898947510087682

Researchgate.net/publication/339628720_A_new_species_of _Allobates_from_Southwestern_Amazonian_highlands