Key to the Ophiodes (Squamata: Sauria: Diploglossidae) of Paraguay with the description of a new species.

Ophiodes is a South American genus of legless diploglossid lizards. Four species have been formally described: O. intermedius, O. vertebralis, O. striatus, and O. fragilis; three additional species were described but not officially named in an unpublished dissertation. These species are referred to as Ophiodes sp. "1", Ophiodes sp. "2", and Ophiodes sp. "3". We recognize five species of Ophiodes in Paraguay, one widespread (O. intermedius) and four known from only one or two localities (O. fragilis, O. striatus, O. sp. "3", and an undescribed species, described herein). The new species described represents the fifth Paraguayan species and the eighth member of the genus. It is distinguished by a combination of the following characters: a high number of middorsal scales between occipital and cloacal opening (>165), 29 scale rows around midbody, the posterior limbs 4 scales long, and vertical black bars on the face absent.

Individualistic population responses of five frog species in two changing tropical environments over time.

Roughly 40% of amphibian species are in decline with habitat loss, disease, and climate change being the most cited threats. Heterogeneity of extrinsic (e.g. climate) and intrinsic (e.g. local adaptations) factors across a species' range should influence population response to climate change and other threats. Here we examine relative detectability changes for five direct-developing leaf litter frogs between 42-year sampling periods at one Lowland Tropical Forest site (51 m.a.s.l.) and one Premontane Wet Forest site (1100 m.a.s.l.) in southwest Costa Rica. We identify individualistic changes in relative detectability among populations between sampling periods at different elevations. Both common and rare species showed site-specific declines, and no species exhibited significant declines at both sites. Detection changes are correlated with changes in temperature, dry season rainfall, and leaf litter depth since 1969. Our study species share Least Concern conservation status, life history traits, and close phylogenetic relationship, yet their populations changed individualistically both within and among species. These results counter current views of the uniformity or predictability of amphibian decline response and suggest additional complexity for conservation decisions.

Population trends of the mantled howler groups of La Pacifica, Guanacaste, Costa Rica.

A complete survey of La Pacifica in Guanacaste Province, Costa Rica was conducted in July 1984 in order to determine whether the howler (Alouatta palliata) population had declined since 1972 as a result of deforestation. During the 6-day survey, 257 howlers were located, representing 16 different social groupings and nine solitary animals. The total number of howlers, the number and location of groups, and the age-sex composition were very similar to a 1972-1976 survey of the same population. Age-sex composition of La Pacifica howler groups was similar to those of another population of mantled howlers in Costa Rica and of populations in Mexico and in Panama, although La Pacifica had a higher mean number of adult females per group. There was no evidence to support the hypothesis that the La Pacifica howler population has declined in recent times.