Breeding success of frogs depends, among other factors, on male and female habitat choices, which may be based in part on environmental features that aid offspring survivorship and development. Frogs can respond to habitat features in varied scales, including types of bodies of water and microhabitats within them, and the correspondence between male and female choices may contribute to a successful reproduction. We compared habitat and microhabitat choices by males and females of a Scinax species from the catharinae clade, focusing on microhabitat selection by both sexes, including variation between dry and wet seasons. We also compared the distribution of males and females across a stream size gradient and related their abundance with numbers of tadpoles in each stream to assess successful breeding. We found males and females to be similar in microhabitat preferences, but their abundances did not correlate across streams. Male abundance, however, correlated with number of tadpoles, indicating that number of females may have been underestimated due to their shorter permanence at breeding sites or lower detection probability. Competition and predation did not seem to influence distribution of Scinax gr. catharinae among streams. Male and female Scinax gr. catharinae seem to show highly coordinated responses when selecting breeding habitats and microhabitats, apparently resulting in high breeding success at the study site.

Escaping prey decide whether to enter and how long to stay in refuges. According to refuge-use theory, hiding time increases as costs of emerging increase and costs of staying in refuge decrease. We studied effects of air temperature on probability of entering refuges and the effects of thermal cost on hiding time (duration in refuge). Few striped plateau lizards (Sceloporus virgatus) used refuges at intermediate air temperatures, but most readily entered cool refuges at the lowest air temperatures and relatively warm refuges at higher temperatures. Because running speed in lizards decreases as body temperature decreases, S. virgatus that are cool upon morning emergence presumably reduced their probability of being captured by entering refuges. As air and presumably body temperatures increase, refuges are initially cooler than outside, contributing to infrequent use. At higher, but not thermally stressful, temperatures, a greater probability of using refuges may reflect lower thermal costs in refuges that have warmed. Hiding time decreased as temperatures became cooler in refuges than outside. Our results confirm previous work on actively foraging lacertid lizards showing that hiding time decreases as thermal costs of refuge use increases, and extend this finding to a very distantly related phrynosomatid species that is an ambush forager. Thus, the thermal cost of refuge use affects hiding time even in lizards that do not require high body temperature for prolonged foraging movements. A growing body of knowledge supports the hypothesis that tradeoffs between costs of emerging and remaining in refuges guide decisions about hiding time.

Time- and context-dependent nest site selection of a phytotelm-breeding frog (Kurixalus eiffingeri) was evaluated in a natural bamboo habitat in subtropical Taiwan from 2004 to 2005. At the beginning of the breeding season (mid-March), frogs preferred bamboo stumps with large water holding capacity, which may be considered high-quality stumps since water availability is critical to the survival of tadpoles. Prior to 21 May, no tadpole-occupied stumps were re-used even though they represented 10–40% of total stumps at the study site; however, tadpole-occupied stumps were consistently re-used afterwards. Stumps with fewer tadpoles were used proportionally more than those with more tadpoles. By choosing the stumps with fewer tadpoles, the negative competitive effect of the late-clutch tadpoles on the early-clutch tadpoles would be somewhat alleviated. Male frogs did not breed in the same bamboo stump for consecutive breeding events, which may relate to the male reproductive strategy. We propose that it would often be a better strategy for a male frog to breed in different stumps than to stay in the same stump, even if the stump was of high quality. Breeding in multiple stumps would increase the number of breeding opportunities by reducing the interval between successive mating attempts, minimize the inter-clutch competition between tadpoles, and avoid competition between two cohorts of its own genetically-related tadpoles. Our results suggest that stump quality is indicated by water holding capacity and the number of the tadpoles in the stump during early and late breeding seasons. Thus, oviposition site choice in this species is dependent on stump quality, but stump quality is both context- and time-dependent.

On the basis of new characters, I reevaluated species groups of Dipsas. A new species described from the Serranía de la Macarena, Colombia, resembles species of the D. articulata and D. pratti groups. I redescribe D. temporalis based on new material and identify apomorphic characters shared between D. temporalis, D. pakaraima, and D. vermiculata. Dipsas incerta is a species distinct from D. copei, although it may be a synonym of another species, most likely D. praeornata. Neotypes recently designated for D. incerta and D. alternans violate qualifying conditions of article 75 of the International Code of Zoological Nomenclature and are invalid. Characters of visceral morphology improve our understanding of dipsadine relationships. Within Dipsas, I recognize eight species groups and propose a new key to the South American species.

Cycloramphus jordanensis was described based on a single preserved specimen from Campos do Jordão (22° 44′ S, 45° 35′ W), State of São Paulo, Brazil. While examining the holotype; we noticed the presence of toe and tarsal fringes. Because these characters are absent in Cycloramphus, we suspected that the species was mistakenly placed in the genus. X-ray images of the holotype revealed T-shaped terminal phalanges and fang-like teeth. Together with the presence of toe and tarsal fringes, these characters squarely place the specimen in the genus Megaelosia. Considering the striking niche differences between Cycloramphus and Megaelosia, we expect the new combination will facilitate location of new individuals of this rare frog.

We describe two new species of Liolaemus belonging to the montanus series. The new species are closely related to L. dorbignyi, but are disjunctly distributed with respect to this taxon. Both new species exhibit unique color patterns, which, along with differences in squamation, differentiate the two new taxa from the other species in the series. Both new species are saxicolous and inhabit rocky hills in the Puna regions of northwestern Argentina. One occurs in the Cerro de la Virgen, Nevados de Cachi and Nevados de Palermo of Salta Province. The other is known only from its type locality in the Cerro El Pichao of Tucumán Province.

Hyalinobatrachium orientale has a complex taxonomic history suggesting that more than one species could be under this name. In this review, we try to clarify the current taxonomic status of this species by means of morphological, bioacoustic, and mitochondrial DNA sequence comparisons of specimens from Tobago Island and the Venezuelan Cordillera de la Costa (Oriental Sector, Cordillera del Litoral and Cordillera del Interior). Our data support the resurrection of Hyalinobatrachium orocostale, restricted to the Cordillera del Interior. Additionally, specimens from Cordillera del Litoral and Oriental Sector do not form a monophyletic group; hence, we define as Hyalinobatrachium sp. the populations from Cordillera del Litoral and H. orientale sensu stricto the populations from the Oriental Sector. Preliminary bioacoustic and morphological analyses indicate that the populations from Tobago are conspecific with Hyalinobatrachium orientale sensu stricto.