The geographic range of sea kraits encompasses one of the geologically most-complex regions of the world. At its center lies Wallacea (the transition between the terrestrial biotas of the Asian and Australian tectonic plates) and the Indonesian Throughflow (nexus of the equatorial marine biotas of the Indian and Pacific oceans). The aim of this study was to elucidate the role of paleogeography, paleoclimatology, and oceanic currents in the evolution and distribution of sea kraits across these major biogeographic crossroads and beyond. A recent assessment of times of taxonomic divergence was projected against paleogeographic reconstructions to produce a parsimonious, hypothetical model of events critical for the origin, dispersal, and differentiation of this taxon. Times and degree of divergence of taxa suggested by recent morphological and molecular studies are in accord with various climatological and geologic events. The model postulates that the distribution of sea kraits was neither greatly affected by tectonics, other than the approach of the Australian Plate to the Asian one, nor dominated by the historic barriers to dispersal of terrestrial fauna across Wallacea, or by the Indonesian Throughflow. Rather, the model suggests that two major factors—paleogeographic alteration of the configuration of land and sea, and the directions of sea currents, past and present—provide an explanation of how these amphibious snakes (1) originated from a terrestrial Asian elapid ancestor, (2) subsequently generated the venomous Australian land snakes and their derivatives the true sea snakes, and (3) differentiated into the species complexes, species, and infraspecific entities of the genus Laticauda.

The Eurycea quadridigitata complex is currently composed of the nominate species and E. chamberlaini, with no other species recognized. However, recent molecular studies have revealed at least five genetic lineages within this species complex, with one lineage more closely related to the neotenic Eurycea species of central Texas and E. chamberlaini nested within E. quadridigitata sensu lato. We use large-scale geographic sampling in combination with a multilocus species delineation method and morphology to test whether these genetic lineages represent distinct species under the general lineage concept of species. We describe two new species of salamander from this complex, resurrect and elevate a former subspecies to full species status, add to the diagnosis of E. chamberlaini, and redefine E. quadridigitata in the context of this revision. All five species are diagnosable from one another through a number of meristic, morphometric, molecular, and ecological criteria.

Eastern Kingsnakes (Lampropeltis getula) are an important component and predator in herpetofaunal communities, but many Eastern Kingsnake populations have declined precipitously in the last few decades, particularly in the southeastern United States. Here, we describe an intensive capture–mark–recapture study of L. getula conducted during 1974–1978 in a canal bank–Water Hyacinth (Eichhornia crassipes) community at Rainey Slough in southern Florida, where annual capture probabilities of adults ranged from 0.662–0.787. Population size and structure, seasonal activity, movements, microhabitat use, behavior, thermal ecology, and predator–prey relationships are described. At this site kingsnakes were susceptible to capture mostly in winter and spring, were diurnal, used rodent (Sigmodon hispidus) burrows on canal banks as nocturnal retreats, and emerged from burrows on 13–26% of the sampling days. Overlap of burrow use by both sexes was extensive with no evidence of territoriality. Kingsnakes readily entered the Water Hyacinths to bask, pursue mates, and forage. At Rainey Slough only snakes were detected in the diet of kingsnakes. Concurrent sampling of potential snake prey in the hyacinths and on canal banks revealed 10 species that varied in use of the two sampled habitats and in body size. A range-wide analysis confirmed that in descending order snakes, reptile eggs, and lizards dominate the diet of L. getula in Florida (94.8%) and remain important prey types elsewhere (80.2%). At Rainey Slough the density of six species of semiaquatic snakes in Water Hyacinths averaged 3534 individuals/ha with a mean annual biomass of 135.8 kg/ha, and kingsnake biomass was only 2.2–3.9% of prey snake biomass. We estimated that the kingsnake population consumed 36.82–63.58 kg/yr, or about 10.0–17.2% of the standing crop of snakes in the Water Hyacinth community. Adult male L. getula lost on average 39.3% of their body mass associated with the spring reproductive season, whereas females lost only 3.4% in the same period. Body condition indices for both sexes improved substantially thereafter. In follow-up surveys at Rainey Slough during 2006–2010 no kingsnakes were found. Semiaquatic snake densities in the Water Hyacinths were 77.2% lower (807.4/ha) than in the 1970s and consisted of only three species. Compared to the enigmatic declines and extirpation of L. getula populations elsewhere, at Rainey Slough the primary cause likely was unsustainable mortality from road reconstruction and paving in the winter–spring of 1979 and subsequent roadkill. Other potentially causative agents of extirpation of L. getula in this system are discussed.

We discovered new populations of Dendragama at the northern and southern ends of Sumatra. High genetic distances and concordance of multiple, apparently independent diagnostic characters support our descriptions of these two populations as new species. We define new characters of the sublabial, tympanic, dorsal crest, and dorsolateral crest scales. The three species of Dendragama undergo remarkable color change in response to time of day and stress. Females lay 2–4 ovoid eggs, reach sexual maturity at about 60 mm snout–vent length, and likely produce multiple clutches each year. We remove Salea rosaceum Thominot from the synonymy of Dendragama boulengeri and argue that the unique holotype of S. rosaceum is a specimen of Pseudocalotes tympanistriga with incorrect locality information.

This paper is the first taxonomic treatment of Sumatran Philautus since the early 20th century. We redescribe P. cornutus and P. petersi from new specimens, restrict P. petersi to Great Natuna Island, and reinstate the name P. larutensis for the populations on Borneo, Peninsular Malaysia, and Sumatra. We then synonymize P. similis with P. larutensis. We report Sumatran populations of P. kerangae and P. refugii, two species previously thought to be endemic to Borneo and discuss the presence of P. aurifasciatus on the island. We describe four new species of Philautus collected during large-scale herpetological surveys of Sumatra between 2013 and 2015 and propose a hypothesis of their relationship to the other Sunda Shelf Philautus on the basis of 16S ribosomal ribonucleic acid sequences. Additionally, we provide a key to the Philautus of Sumatra. In the course of this work we transfer P. vittiger from Java to the genus Chiromantis.

Our study represents the first attempt to describe biogeographic provinces for North American (México, United States, and Canada) turtles. We analyzed three nested data sets separately: (1) all turtles, (2) freshwater turtles, and (3) aquatic turtles. We georeferenced North American turtle distributions, then we created presence–absence matrices for each of the three data sets. We used watershed unit as biogeographic units. We conducted an unweighted pair-group method with arithmetic mean clustering analysis on each Jaccard index distance matrix from our watershed species matrices to delineate biogeographic provinces. Provinces were then tested for significant differences in species compositions in a global model with the use of a one-way analysis of similarity. We conducted a best subset of environmental variables with maximum (rank) correlation with community dissimilarities that determined the best model of abiotic variables explaining province delineation (i.e., climate, topography, and stream channel). To identify which species contributed the most to province delineations, we conducted an indicator species analysis and a similarity-percentage analysis. There were 16 all-turtle provinces, 15 freshwater provinces, and 13 aquatic provinces. Species compositions delineating the provinces were explained by abiotic variables, including mean annual precipitation, mean precipitation seasonality, and diversity of streams. Province delineations correspond closely with geographical boundaries, many of which have Pleistocene origins. For example, rivers with a history of carrying glacial runoff (e.g., Arkansas, Mississippi) sometimes dissect upland provinces, especially for aquatic and semiaquatic turtles. Compared with freshwater fishes, turtles show greater sensitivity to decreased temperature with restriction of most taxa south of the last permafrost maximum. Turtles also exhibit higher sensitivity to climatic, geomorphic, and tectonic instability, with richness and endemism concentrated along the more stable Gulf of México and Atlantic (south of the last permafrost maximum) coasts. Although distribution data indicate two aquatic turtles are most cold tolerant (i.e., Chrysemys picta, Chelydra serpentina), aquatic turtles overall show the most restriction to warmer, wetter climates. Sequential addition of semiaquatic and terrestrial turtles into analyses shows, as expected, that these taxa flesh out turtle faunas in climatically harsh (e.g., grasslands) or remote (e.g., California, Sonoran Desert) regions. The turtle assemblages of southwestern versus southeastern North America are distinct. But there is a transition zone across the semiarid plains of the Texas Gulf Coast, High Plains, and Chihuahuan Desert, including a strong boundary congruent with the Cochise Filter-Barrier. This is not a simple subdivision of Neotropical versus Nearctic taxa, as some lineages from both realms span the transition zone.

Size and shape of sensory organs are features, among others, that can affect sensory functioning. Natural selection can act on such features to optimize performance in particular environments and for particular life histories and behavioral repertoires, although selection is not the only force influencing a particular structure. I examined olfactory and vomeronasal organ morphology in several species of salamanders in the Family Plethodontidae ranging from completely aquatic, semiaquatic, terrestrial, to arboreal. The Plethodontidae is the most speciose and diverse urodele group, making it a particularly interesting subject of evolutionary study. I examined microanatomy with the use of serial sections of complete snouts of species from the Appalachians and Neotropics, the two centers of plethodontid diversity. All species, except the aquatic Desmognathus marmoratus, had thick olfactory epithelia very anteriorly in the snout, especially mid-point in the main olfactory chamber, which may optimize odorant delivery along the path of airflow in through the external nares and out through the internal nares. Desmognathus marmoratus had greatly reduced olfactory epithelia. All species had well developed vomeronasal organs, particularly Desmognathus species, indicating the importance of this system for plethodontids. Small species had nasal chambers organized to optimize space for both olfactory and vomeronasal epithelia, and all Neotropical species had particularly thick sensory epithelia; these may be compensatory mechanisms to ensure adequate sensory receptor cell numbers in small snouts and/or with large cell sizes. A number of different gland types, including nasal, intermaxillary, nasochoanal, nasolabial, vomeronasal, and orbital, occupy a large and variable space within rostra, and their functions warrant further investigation. Chemoreception and vision are the two most important sensory modalities for plethodontids, and the simpler organization of chemosensory systems compared to vision, and compared to chemoreception in other vertebrates, make plethodontids attractive subjects in the study of the evolution of chemosensory systems.

With a published multilocus phylogenetic analysis as our guide, we use new data from the external phenotype and genetically defined distributions of evolutionary lineages to resolve species boundaries associated with the southwest Mindanao Stream Frogs, Sanguirana everetti (Boulenger 1882), its junior synonym, Rana mearnsi, Stejneger 1905, and the northeast Mindanao Stream Frogs, Sanguirana albotuberculata (Inger 1954). Consideration of relationships, distributions, type localities, phenotypic data, and type specimens clearly indicates that the names R. mearnsi and S. albotuberculata refer to the same lineage, and we recognize the oldest available name (Sanguirana mearnsi) for this species. We also define the central Philippine lineage (from Negros, Masbate, and Panay islands) as a distinct new species. Long confused with S. everetti, the new taxon is readily diagnosed and biogeographically restricted to the West Visayan faunal region. The new multilocus estimate of phylogeny and our multivariate analysis of morphological variation demonstrate that the new species is closely related and phenotypically most similar to northern Philippine Sanguirana luzonensis, to the exclusion of S. everetti, the southern species with which it previously was confused. Morphological characters distinguishing the new species include body size, the absence of infracloacal tubercles, the presence of smooth dorsal skin without dorsolateral folds or dermal asperities, its degree of sexual size dimorphism, uniquely stratified flank coloration, bright white subarticular tubercles, bold pectoral patches, dark transverse bars on the limbs, and various body proportions. Recognition of this new species further emphasizes the predictable nature of island bank-structured endemism in the Philippines and demonstrates that the country's vertebrate diversity remains underestimated. The new species is relatively rare, patchily distributed and, with so little natural forest remaining in the central Philippines, it constitutes an immediate conservation concern. Management of this problem will require continued, field-based collection of data on the new species, distribution, local abundance, population trends, natural history, reproductive biology, and larval ecology—most of which currently is unknown.