Rediscovery and phylogenetic position of the glassfrog "Centrolene"acanthidiocephalum (Ruiz-Carranza and Lynch, 1989) (Anura: Centrolenidae)with the description of its advertisement call and comments on clutches and tadpoles

The lack of basic natural history and distributional data represents a challenge for the conservation of rare and endemic amphibian species. This is the case of "Centrolene" acanthidiocephalum, a poorly known glassfrog endemic to the Cordillera Oriental of the Colombian Andes. This species was formally described in the late 1980s and no records have been reported over the last quarter century. Therefore, little is known about its distributional boundaries, morphological variation, natural history, and evolutionary relationships. Here we report the finding of a population of "Centrolene" acanthidiocephalum from a locality around its historical range and provide additional information on its geographic distribution, clutch size, and adult morphology. We also present for the first time data on tadpole morphology, as well as a description of its advertisement call and a phylogenetic tree based on mitochondrial genetic data corroborating its generic position within Centrolene.

The poverty of adult morphology: Bioacoustics, genetics, and internal tadpole morphology reveal a new species of glassfrog (Anura: Centrolenidae: Ikakogi) from the Sierra Nevada de Santa Marta, Colombia

Ikakogi is a behaviorally and morphologically intriguing genus of glassfrog. Using tadpole morphology, vocalizations, and DNA, a new species is described from the Sierra Nevada de Santa Marta (SNSM), an isolated mountain range in northern Colombia. The new taxon is the second known species of the genus Ikakogi and is morphologically identical to I. tayrona (except for some larval characters) but differs by its genetic distance (14.8% in mitochondrial encoded cytochrome b MT-CYB; ca. 371 bp) and by the dominant frequency of its advertisement call (2928-3273 Hz in contrast to 2650-2870 Hz in I. tayrona). They also differ in the number of lateral buccal floor papillae, and the position of the buccal roof arena papillae. Additionally, the new species is differentiated from all other species of Centrolenidae by the following traits: tympanum visible, vomerine teeth absent, humeral spines present in adult males, bones in life white with pale green in epiphyses, minute punctuations present on green skin dorsum, and flanks with lateral row of small, enameled dots that extend from below eye to just posterior to arm insertion. We describe the external and internal larval morphology of the new species and we redescribe the larval morphology of Ikakogi tayrona on the basis of field collected specimens representing several stages of development from early to late metamorphosis. We discuss the relevance of larval morphology for the taxonomy and systematics of Ikakogi and other centrolenid genera. Finally, we document intraspecific larval variation in meristic characters and ontogenetic changes in eye size, coloration, and labial tooth-rows formulas, and compare tadpoles of related species. Ikakogi tayrona has been proposed as the sister taxon of all other Centrolenidae; our observations and new species description offers insights about the ancestral character-states of adults, egg clutches, and larval features in this lineage of frogs.

Community assembly of glass frogs (Centrolenidae) in a Neotropical wet forest: a test of the river zonation hypothesis

The river zonation hypothesis predicts that abiotic and biotic conditions along riparian gradients drive variation in animal communities. Glass frogs are a diverse group of Neotropical anurans that use riparian habitats exclusively for oviposition and larval development, but little is known about how glass frog communities are distributed across riparian gradients. Here, we measured glass frog community assembly across a gradient of riparian habitats from first- to fifth-order streams at La Selva Biological Station, Costa Rica. We performed repeated nocturnal frog calling surveys and built occupancy andN-mixture abundance models to test for varying patterns of species occupancy, community assembly, species richness (α-diversity) and species turnover (ß-diversity). We observed significant differences in patterns of species occupancy and community assembly across a stream-order gradient: occupancy of two species increased with stream order (Teratohyla pulverata,Hyalinobatrachium fleischmanni), one species decreased (Teratohyla spinosa), and one species did not vary (Espadarana prosoblepon). We evaluated four a priori hypotheses describing how α- and ß-diversity of centrolenids are shaped across the riparian gradient; our data were most consistent with a pattern of nested assemblages and increasing species richness along the riparian gradient. Species-specific patterns of occupancy and abundance resulted in assemblage-level differences consistent with theoretical predictions for highly aquatic organisms along riparian gradients.