SYSTEMATICS OF THE ELEUTHERODACTYLUS FRAUDATOR SPECIES GROUP (ANURA: BRACHYCEPHALIDAE)

A new cryptic species of terrestrial breeding frog of the Pristimantisdanae Group (Anura, Strabomantidae) from montane forests in Ayacucho, Peru

Based on morphological and molecular characters, we describe a new species of terrestrial breeding frog of the Pristimantisdanae 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, Pristimantispharangobates and Pristimantisrhabdolaemus. 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 Batrachochytriumdendrobatidis (Bd) in this species.

New phenotypic synapomorphies delimit three molecular-based clades of New World direct-developing frogs (Amphibia: Anura: Brachycephaloidea)

Brachycephaloidea (composed of 1183 species) is the most diverse superfamily of amphibians. In recent years, molecular techniques utilizing genetic markers have significantly improved our understanding of the phylogeny of this superfamily. However, with the expansion of molecular techniques, phenotypic characters have received increasingly less attention. In an effort to highlight the contributions that phenotypic characters can make to understanding the phylogeny of Brachycephaloidea, we studied novel characters from pelvic and thigh musculature and digital discs on fingers. On this basis, we provide new phenotypic synapomorphies to recognize three clades previously recognized solely on the basis of DNA. The first two synapomorphies, related to the origins of the m. iliacus externus and m. tensor fasciae latae, diagnose Ceuthomantis and Phrynopus, respectively. The third synapomorphy, related to the relative size of the disc on finger I, diagnoses the Pristimantis conspicillatus species group, which is the largest species group within the species-rich genus Pristimantis. We conclude that phenotypic data are a valuable source of evidence in testing phylogenetic hypotheses of Brachycephaloidea and emphasize the need to reassess all phenotypic characters previously used in brachycephaloid taxonomy to delimit them objectively as transformation series and include them in total evidence analyses.

A new small golden frog of the genus Pristimantis (Anura: Craugastoridae) from an Andean cloud forest of Colombia

A new species ofPristimantisis described from an Andean cloud forest at 2650 m in the Cordillera Oriental of Colombia.Pristimantis doradosp. nov. is similar to and could be closely related toP. acutirostris, but can be readily distinguished from this latter species by the absence of a tympanic annulus, vocal slits, vocal sac and reticulations on concealed surfaces, and by having a metallic gold iris with a brown horizontal streak. The phylogenetic position of the new species is recovered and we provide its advertisement call, which this species manages to emit despite lacking a vocal sac and vocal slits. This discovery reminds us that despite the extensive research on the alpha-taxonomy ofPristimantisin Colombia, fieldwork in high montane forests continues to yield previously unknown species.

The Great American Biotic Interchange in frogs: multiple and early colonization of Central America by the South American genus Pristimantis (Anura: Craugastoridae)

The completion of the land bridge between North and South America approximately 3.5-3.1 million years ago (Ma) initiated a tremendous biogeographic event called the Great American Biotic Interchange (GABI), described principally from the mammalian fossil record. The history of biotic interchange between continents for taxonomic groups with poor fossil records, however, is not well understood. Molecular and fossil data suggest that a number of plant and animal lineages crossed the Isthmus of Panama well before 3.5 Ma, leading biologists to speculate about trans-oceanic dispersal mechanisms. Here we present a molecular phylogenetic analysis of the frog genus Pristimantis based on 189 individuals of 137 species, including 71 individuals of 31 species from Panama and Colombia. DNA sequence data were obtained from three mitochondrial (COI, 12S, 16S) and two nuclear (RAG-1 and Tyr) genes, for a total of 4074 base pairs. The resulting phylogenetic hypothesis showed statistically significant conflict with most recognized taxonomic groups within Pristimantis, supporting only the rubicundus Species Series, and the Pristimantis myersi and Pristimantis pardalis Species Groups as monophyletic. Inference of ancestral areas based on a likelihood model of geographic range evolution via dispersal, local extinction, and cladogenesis (DEC) suggested that the colonization of Central America by South American Pristimantis involved at least 11 independent events. Relaxed-clock analyses of divergence times suggested that at least eight of these invasions into Central America took place prior to 4 Ma, mainly in the Miocene. These findings contribute to a growing list of molecular-based biogeographic studies presenting apparent temporal conflicts with the traditional GABI model.