Thresholds for evoked advertisement calling for 18 males were measured in a temperate forest in southern Chile, in order to relate this behavior to the intensities of neighbors' calls that males of this species encounter in nature. Stimuli used were bouts of natural single-note advertisement calls played back at increasing intensity in steps of 6–12 dB. Male frogs responded with single-note advertisement calls to stimulus bouts at average sound levels of about 60 dB peak SPL (range: 39–85 dB peak SPL), measured at the subjects' position. Frogs increased their call rates in response to increasing stimulus intensity, reaching a plateau at about 24 dB above threshold. At intensities above threshold, 11 frogs also responded with double-note calls, and two of these frogs occasionally gave triple- and four-note calls. The average thresholds for advertisement calling are low enough so that males respond to their nearest neighbors in low-density aggregations, thereby sustaining the chorusing activity.

The embryonic stage in the red-crowned toadlet (Pseudophryne australis) varies among individuals of a clutch in three important features that may be a source for selection: the length of the embryonic period (15–119 days), the stage of development at which hatching occurs (Gosner 24–36) and the size of the tadpole at hatching (21–97 mg). Previous evidence suggests that variation in the stage at hatching and the length of the embryonic period is not a facultative response to environmental cues. To ascertain whether the basis for this variation was differential maternal provisioning, we investigated the amount of variability in egg sizes, and then the relationship of egg size to the length of embryonic period, stage and mass at hatching. The mean coefficient of variation in egg sizes was 3.9% (range 2.5–8.5%), which is quite high when compared to other amphibians. Egg size was positively related to tadpole size at hatching, and this may have consequences for fitness. No relationship was found between egg size and stage at hatching. The relationship between egg size and length of embryonic period varied among clutches, with significant sibship effects evident. The basis for variation in stage at hatching and length of embryonic period remains unknown, but could relate to factors such as the nutritive value of yolk independent of egg size or possibly genetic factors.

Effective amphibian conservation must consider population and landscape processes, but information at multiple scales is rare. We explore spatial and temporal patterns of breeding and recruitment by eastern spadefoot toads (Scaphiopus holbrookii), using nine years of data from continuous monitoring with drift fences and pitfall traps at eight ephemeral ponds in longleaf pine-wiregrass sandhills. Breeding events (≥25 adults at a pond within a month) occurred 23 times on nine occasions at seven of the eight study ponds, but substantial recruitment (≥100 metamorphs) followed only five events. Recruitment ranged from 0–4648 among ponds. Only four ponds functioned as population “sources”, and only during some years. The other ponds, and even “source” ponds during some years, functioned either as “sinks,” where breeding occurred with no resulting recruitment, or were not used at all for breeding. Most recruitment occurred during four years. Recruitment was correlated with adult breeding effort, but only during some years. Recaptures were rare, and inter-pond exchange of adults was minimal and short-distance (<130 m; one was 416 m). Most (83.5%) individuals captured were metamorphs, and 15.9% were ≥51 mm (est. ≥4 yr). We conservatively estimated a 7-yr lifespan. Adult “population” trends clearly reflected breeding effort rather than numbers per se; capture rates fluctuated dramatically among years, but showed no overall trends during the 9-yr study. Our paper is provides empirical information that can be used to generate realistic metapopulation models for S. holbrookii as a tool in conservation planning.

Previous research has shown that red-backed salamanders (Plethodon cinereus) are able to detect the unseen presence of conspecifics through pheromones left on the substratum. We conducted an experiment with territorial males to determine if they can also detect volatile (or airborne) components of pheromones from male and female intruders. By placing pheromone-laden substrata from source males and females inside or outside a perforated Petri dish, we found that males respond aggressively towards male pheromones inside the dish relative to a control and nose tapped dishes containing both source males' and females' pheromones more than the control. We did not find evidence that residential males could differentiate between volatile components of males' and females' pheromones, but they responded more aggressively towards males' than towards females' pheromones when they had direct access to pheromone-laden substrata. These data suggest that territorial males need not patrol their small territories in search of intruders but can detect such intruders through volatile components of their pheromones. Direct contact with pheromones on the substratum may be necessary for males to differentiate between male and female intruders.

We measured the critical thermal maxima (CTMax) of tadpoles of Buergeria japonica inhabiting streams and geothermal hot springs. The CTMax of all B. japonica tadpoles was over 41 C, indicating that the tadpoles are heat-tolerant. At Rushan, we monitored the temporal and spatial distribution of tadpoles over a 24-h period in a 220 cm × 70 cm plot that is fed by a geothermal hot spring. The thermal profiles of the plot varied seasonally, but the highest water temperature selected by tadpoles remained similar (ca. 37 C). In the winter, the thermal range of the plot was lower (29.5–40.6 C), and tadpoles could be found in the majority of the plot. In contrast, during the spring and summer the temperature ranges of the plot were higher (33.1–43.8 C and 33.0–42.4 C, respectively), and tadpoles could be found only in the cooler sections of the plot, especially around 1000 h with direct solar radiation. These results suggest that extreme heat tolerance and behavioral thermoregulation (i.e., heat avoidance behavior) are the main means by which B. japonica tadpoles cope with the high temperatures in geothermal hot springs.

In the present paper, (a) I discuss the validity of the name Lacertus mabouya Lacepède, 1788 (currently placed in the genus Mabuya Fitzinger, 1826); (b) I designate a neotype for this West Indian species; and (c) I describe this neotype, which differs from Mabuya sloanii (Daudin, 1802) on several morphological characters. This work is a first step toward revising the neotropical members of the genus Mabuya.

We examined allozymic variation in Hynobius boulengeri, H. stejnegeri, and an unidentified salamander from Amakusa Island, to elucidate the evolution of these salamanders within Kyushu, southern Japan. We found three genetic groups in Kyushu: (1) H. boulengeri from the Sobo-Katamuki Mountains, (2) H. stejnegeri from the Kyushu Central Mountains, and (3) H. boulengeri from the Osumi Peninsula and the salamander from Amakusa Island. Collectively, these three groups formed a clade that was genetically very remote from H. boulengeri from Shikoku and Honshu. The salamander from Amakusa Island was genetically very close to the southernmost populations of H. boulengeri from the Osumi Peninsula and was judged to be a population of the Kyushu group of H. boulengeri. Hynobius stejnegeri also proved to be genetically very close to the Kyushu populations of H. boulengeri, and was assumed to represent one lineage, which attained its unique amber body color in the course of differentiation from the ancestral Kyushu stock of H. boulengeri. The three genetic groups are surmised to have been isolated to their present ranges as a result of geohistoric events within Kyushu Island.

Hyla circumdata (Cope, 1870) occurs in subtropical and tropical rain forests, distributed over mountain ranges of the Brazilian Plateau, mainly in the Serra do Mar and Serra da Mantiqueira ranges. Samples of the northern sector of Serra da Mantiqueira revealed distinctive characters when compared to samples from the southern sectors of Serra da Mantiqueira and Serra do Mar, which suggest that the former is a new species. The new species is characterized mainly by large size (snout–vent length 57.5–70.0 mm in males; 55.3–67.2 mm in females), absence of vocal slits in adult males, and a large tympanum.

A new species of the Scinax catharinae group is described from Misiones, northeastern Argentina. It is characterized by the dark yellow flash colors in hidden areas of thigh and shank; robust but not hypetrophied forearm; and lack of a thick glandular patch in the inguinal region. It is closely related to Scinax berthae, from which it can be distinguished by having a more robust forearm and less toe webbing. In addition, relative to S. berthae, males of the new species are slightly larger and the few known females are notably larger.

I describe a new species of Stenocercus from the lowlands of southwestern Ecuador and northwestern Peru. The new species differs from other Stenocercus by the combination of the following characters: posterior circumorbitals present, one row of supraoculars enlarged, posterior head scales enlarged, projecting angulate temporals absent, canthals two, ventrals smooth, posthumeral and postfemoral mite pockets shallow, dorsolateral crests absent, inscriptional ribs not articulating midventrally, throat yellow and venter lavender in males. Some evidence suggests that the new species is closely related to Stenocercus iridescens, which occurs allopatrically in the lowlands of western Ecuador and southwestern Colombia.