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Mesoclemmys dahliandM. zuliaeare two endangered, little-known toad-headed turtles with small distribution ranges in Colombia and Venezuela, respectively. Using the mitochondrial cytochromebgene as a marker, we investigate their phylogeographic differentiation. Furthermore, based on 2341 bp of mtDNA and 2109 bp of nDNA ofM. dahli,M. zuliaeand allied chelid turtles, we infer their divergence time using a fossil-calibrated relaxed molecular clock approach.Mesoclemmys dahliandM. zuliaeare closely related species, with an estimated mean divergence time of 10.6 million years. This estimate correlates with the uplift of the Serranía de Perijá, an Andean mountain chain separating their distribution ranges, suggesting that this event could have caused the evolution of the two species. Haplotype and nucleotide diversities ofM. dahliare markedly higher than inPodocnemis lewyana, another endemic turtle species of Colombia. This pronounced dissimilarity may reflect differences in the phylogeographies and demographic histories of the two species, but also different habitat preferences.

Taxonomy. -Mesoclemmys dahli was originally described as Phrynops (Batrachemys) dahli by Zangerl and Medem in 1958, based on four specimens collected "near" Sincelejo, Sucre, Colombia. The epithet honors the collector, ichthyologist, and professor George Dahl from the Liceo Bolivar of Sincelejo. Medem (1966) later published data on the ecology and behavior of the species and provided information regarding its geographic range. Additionally, he collected a few more individuals that are deposited at the Instituto de Ciencias Naturales of the Universidad Nacional de Colombia.For many years the taxon was referred to as simply Phrynops dahli, as the use of subgenera did not gain wide acceptance. McCord et al. (2001) conducted a study of the broad genus Phrynops and suggested resurrecting and elevating the old subgenus Batrachemys, designating the species Batrachemys dahli. Their analyses were not accepted by some authors (Joyce et al. 2004 and others), mainly because the phylogenetic relationships of South American chelids are not well resolved, and the species was subsequently placed in the broader genus Mesoclemmys, also an old subgenus of Phrynops. Vargas-Ramírez et al. (2012) analyzed sequences of the mitochondrial cytochrome b gene and identified a close relationship and weak genetic divergence between M. dahli and M. zuliae from Venezuela. Currently, the Turtle Taxonomy Working Group (2012) recognizes the species as Mesoclemmys dahli.Description. -Mesoclemmys dahli is a small to medium-sized freshwater turtle. Maximum carapace length (CL) is 297 mm recorded from a female from Cesar. The species is characterized by having a proportionally large head with a pointed snout and a relatively thin and very long neck; tympanic head width is 23-26% of the carapace length (Rueda-Almonacid et al. 2007).

Relaciones espaciales y alimenticias del ensamblaje de Reptiles del complejo cenagoso de Zapatosa, depaRtamento del cesaR (colombia) guido Fabian medina-Rangel 1,2 gladys cáRdenas-áRevalo 1 ABSTRACT To find environmental factors that favors richness and abundance of species and groups of reptiles, his preference for microhabitats, species diet and differences between habitats in parameters such as size of individuals, level of detection and proportion of predation, we made four field trip in surrounding areas of the Zapatosa's wetland complex, between November of 2006 and October of 2007, embracing both the rainy and the dry season Habitats with significant differences between environmental and structural variables were riparian forest, palm-grove, tree-lined savanna and chasmophyte forest; riparian forest and dry forest were not different. The slope of the land and degree of human intervention were variables more related to species abundance. By increasing the slope and human intervention, the richness and abundance of reptiles in general and snakes and lizards decreased; with the increase of environmental temperature average, abundance of reptiles decreased. With increasing herbaceous cover and decreased tree diameter, the richness of snakes and lizards decreased. The body size of the reptiles was not different between habitats, although small sizes predominated in all. Snakes had lower detection values those lizards. Riparian forest had the highest detection values. A fifth of all lizards showed some sign of predation and was higher in the palm-grove. Terrestrial reptiles were the richest and most abundant in the study. Lizards had the highest amplitude in the habitat use and microhabitat, while snakes Helicops danieli and Leptodeira septentrionalis and lizards Anolis gaigei, Gonatodes albogularis y Cnemidophorus lemniscatus in the food use. Lizards exhibit greater overlap in the use of resources.

We report the first record in Colombia, and the first find since 1966 of Imantodes phantasma Myers, 1982, based on 3 specimens from Unguía municipality, department of Chocó, Colombia. The present record adds a new snake species to the country's list and extends this species' documented distribution by approximately 65 km, in a straight-line northeast from its nearest previously known Panamanian locality. This is the first report of this species for more than 50 years since its description.

This study reports the salamander Oedipina complex (Dunn, 1924) in a tropical and relictual humid forest in the Magdalena Valley, Colombia. Previous records outline O. complex as a species associated with the pluvial forests of central and northern areas of the Chocó Biogeographic Region in Colombia, Ecuador, and Panama. Based on this new record, the geographic distribution of the species is expanded 257 km east.

Geophis nigroalbus Boulenger, 1908 is a fossorial and secretive colubrid snake endemic to the western Andes of Colombia. Here we report this species for the first time in the Cordillera Oriental in Middle Magdalena Valley. We expand the known distribution of G. nigroalbus 183 km east of its original range.