Crossodactylodes is a poorly known genus of small-sized bromeligenous frogs, endemic to Brazil. They have a patchy distribution across the mountains of the Atlantic Forest and the “campo rupestre” ecosystem. To better resolve their evolutionary relationships, we performed phylogenetic analyses using a multigene DNA matrix and representative sampling within the genus. We then evaluated the evolution of phenotypical and natural history traits with the inferred phylogeny. We recovered Crossodactylodes as monophyletic, diagnosed by seven putative synapomorphies in morphological and natural history characters. Evidence supports some morphological synapomorphies as adaptations to the bromeligenous habit. We found high genetic distances among closely distributed lineages within C. bokermanni and C. izecksohni. Some of these lineages might represent undescribed cryptic species. We provide detailed accounts for each species including data on their geographic range, conservation, and natural history. All species of Crossodactylodes occur in highly threatened environments, are restricted to very small geographic ranges, and probably have limited dispersal capacity due to their small body size and dependence on bromeliads. These factors emphasize the need for habitat protection to safeguard species viability.

Species descriptions of reptiles historically have relied exclusively on the use of morphological data; however, these external, phenotypic data do not always co-vary with lineage divergence. Consequently, it has become increasingly clear that species diversity has been underestimated in many evolutionary radiations. With the use of an integrative approach, we examined the genetic and morphological diversity present in a nearly endemic Philippine radiation of Eutropis. Results demonstrated that current taxonomy does not reflect evolutionary history and that in many cases, morphological divergence has become decoupled from genetic divergence. As a consequence, species diversity is significantly underestimated. Here, we rectify the major taxonomic problems present in Philippine Eutropis by providing formal descriptions for eight new species. Three of the four new species in the E. multicarinata species complex are sympatric with (and have long been confused with) previously described subspecies (which we also elevate to full species here). The fourth species is endemic to the Caroline Islands, clearly derived from a long-distance dispersal event from the Philippines. The new species in the E. indeprensa species complex are allopatrically or parapatrically distributed across the archipelago. In contrast to the last review of Philippine Eutropis, which suggested the endemic radiation was composed of five species (one of which was composed of two subspecies), we demonstrate that this group includes at least 14 distinct evolutionary lineages, with potential for additional diversity to be discovered pending further study.

Despite rising interest among scientists for over two centuries, parental care behavior has not been as thoroughly studied in amphibians as it has in other taxa. The first reports of amphibian parental care date from the early 18th century, when Maria Sibylla Merian went on a field expedition in Suriname and reported frog metamorphs emerging from their mother's dorsal skin. Reports of this and other parental behaviors in amphibians remained descriptive for decades, often as side notes during expeditions with another purpose. However, since the 1980s, experimental approaches have proliferated, providing detailed knowledge about the adaptive value of observed behaviors. Today, we recognize more than 30 types of parental care in amphibians, but most studies focus on just a few families and have favored anurans over urodeles and caecilians. Here, we provide a synthesis of the last three centuries of parental care research in the three orders comprising the amphibians. We draw attention to the progress from the very first descriptions to the most recent experimental studies, and highlight the importance of natural history observations as a source of new hypotheses and necessary context to interpret experimental findings. We encourage amphibian parental care researchers to diversify their study systems to allow for a more comprehensive perspective of the behaviors that amphibians exhibit. Finally, we uncover knowledge gaps and suggest new avenues of research using a variety of disciplines and approaches that will allow us to better understand the function and evolution of parental care behaviors in this diverse group of animals.

Chironius bicarinatus is a conspicuous colubrid snake species, widely distributed in northeastern, southeastern, central-western, and southern Brazil, as well as Paraguay, Argentina, and Uruguay. On the basis of new morphological data of individuals from previously unsampled regions and deoxyribonucleic acid sequences, we reviewed the taxonomy of populations previously referred to as C. bicarinatus, revisiting the species definition with an updated diagnosis, inferring its phylogenetic relationships with closely related lineages in southern Brazil, herein described as a new species restricted to Pampa forests or grasslands and Atlantic Forest semidecidual forests in southern Brazil. The new species can be readily diagnosed from C. bicarinatus and all other congeners on the basis of internal (hemipenis unilobed, unicalyculate, cylindrical, apex with smooth calyces, with spinules restricted to proximal portion, near the medial area; lacrimal foramen with small projection on the anteroventral margin) and external morphology (ventrals 153–165 [153–165 in males, 155–164 in females]; subcaudals 103–146 pairs [129–142 in males, 103–146 in females]; adult dorsal pattern with dark green background, scales sometimes with light blue margin, two conspicuous black dorsal stripes with light green vertebral stripe between them that gradually dissipates to the tail, ventrals with black margin on its edges) and molecular evidence.

The Leptodactylus latrans species group currently comprises eight medium- to large-sized frog species with a convoluted taxonomic history, particularly related to the specific limits of the L. latrans complex, and the species pair Leptodactylus chaquensis–Leptodactylus macrosternum. Their homogeneous external morphology and continental geographic distribution in South America have posed severe limitations to a comprehensive review, such that taxonomic consensus and species limits remain uncertain. This is further worsened by the presence of chromatic polymorphism among coexisting species that can hardly be distinguished by external morphology. Based on a large-scale geographic sampling including multilocus DNA analyses, and acoustic and morphological data, we provide a comprehensive evaluation of the taxonomic status and species limits of the L. latrans group, focusing on the resolution of the L. latrans complex and the species pair L. chaquensis–L. macrosternum. We gathered 728 mitochondrial sequences from 429 localities, encompassing the entire geographic distribution of the group. Both generalized mixed Yule coalescent and automatic barcode gap discovery species delimitation methods recovered four major mitochondrial evolutionary lineages within the L. latrans complex, also supported by distribution patterns, multilocus molecular, morphological and/or bioacoustic data. One lineage is linked to nominal L. latrans, one revalidated as Leptodactylus luctator, and the other two are formally named and described. Another lineage encompasses all specimens previously assigned to the species pair L. chaquensis–L. macrosternum, clustered as a single evolutionary entity and is now regarded as L. macrosternum. We provide a revised diagnosis for these species based on acoustic data, morphological/chromatic variation, and phylogenetic relationships of all species currently included in the L. latrans group. Our findings reinforce the view that Neotropical diversity is highly underestimated and stress that appropriate geographic sampling in an integrative framework is crucial for the establishment of specific limits among broadly distributed and morphologically cryptic Neotropical frogs.

Shed skins of snakes have practical applications and can provide information on biodiversity. We examined shed skins or scales stripped from 53 native species of snakes from Taiwan and adjacent islands and 13 foreign species, verified the intraspecific variation of microstructures on the scales, conducted phylogenetic comparative analyses of microdermatoglyphics, and developed a guide and key to identify shed skins by scanning electron microscopy. We examined several microstructural characteristics of scales including the form and dimensions of oberhautchen cells, denticulations, microridges, nanopits, and nanochannels. Furthermore, we noted scale shape and presence or absence of rounded tubercles on the scales. The microstructures of apical (and central) regions of scales were similar to each other, but different from those on basal and lateral margins, the keel, or apical pits. The microdermatoglyphics on cranial scales (cephalic shields) differed from those on scales from other regions of the body. Those from the dorsal and dorsolateral surfaces of the body, and the dorsal surface of the tail were similar, as were those on scales from the ventral surfaces of the body and tail. For adults or juveniles, there was no significant ontogenetic variation in many microdermatoglyphic characteristics. By conducting phylogenetic mapping, we found that symmetrical (dorsal) scales without apical pit organs or rounded tubercles, keelless and rounded scales, flat microdermatoglyphic patterns (without longitudinal microridges), (sub)lamellate oberhautchen cells, cell borders without denticulations or with tiny and keelless denticulations, and relatively small nanopits at denticulation joints or covering cells, are likely to be plesiomorphic character states. We also examined character evolution models based on the microdermatoglyphics and their phylogenetic signals, conducted phylogenetic generalized least-squares regressions to examine the correlations among snake habitat type and the morphological traits on scales, and confirmed a hypothesis that the evolution of scale microstructures is dominated by both phylogenetic and functional (ecological) constraints. This study also indicates that scale microstructure can be used to identify snakeskin products, roadkill specimens and fragmented samples, scale remnants in predator feces, and wild snake sloughs.

The species of the subfamily Uromastycinae are herbivorous burrowing lizards distributed from the African Sahara Desert to the Asian Thar Desert and across the Arabian Peninsula. Although osteological studies on Uromastycinae have a long history, a detailed description of the complete skeleton is lacking. We investigate the cranial and postcranial osteology of the Mesopotamian Spiny-tailed Lizard (Saara loricata, previously referred to Uromastyx). We studied articulated and disarticulated materials from five specimens and present a complete description of the bones of the species. Our study adds to the growing body of literature on the skeleton of agamid lizards. Unlike Uromastyx sensu stricto, in S. loricata no anterior premaxillary foramina exists on the anterior surface of the premaxilla, no contact exists between the frontal and the maxilla or premaxilla, the anterolateral processes of the frontal are unexposed in dorsal view so that the prefrontal and nasal are attached, and the pterygoid does not contact the vomer anteriorly and the quadrate posteriorly. Unlike its congener S. hardwickii, in S. loricata no anterior premaxillary foramen exists on the anterior surface of the premaxilla, a smaller ethmoidal foramen perforates the nasal, a well-developed, posteriorly extended socket-like notch is formed through anterior bifurcation of the jugal, an L-shaped suture line forms between the jugal and postorbital in dorsal view, and an interlocking suture between the surangular and dentary exists in S. loricata.

The Rhinella spinulosa group is a clade of toads that inhabit the Andes mountains from northern Ecuador to Patagonia. Its taxonomy was recently revised, and in its new arrangement comprises nine species, including Rhinella gallardoi, traditionally placed in a different intrageneric group. In this work we studied the larval external and internal morphology in this group, by describing for the first time tadpoles of R. achalensis, R. gallardoi, and R. vellardi, and then summarizing morphological data for R. altiperuviana, R. limensis, R. papillosa, R. spinulosa, and R. trifolium. Although we found no diagnostic larval features for the whole clade, two distinct morphs were identified. Most tadpoles were highly pigmented and slender, and their oral discs showed a long gap in the second labial tooth row; conversely, tadpoles of R. limensis and R. vellardi shared a globose body and a very short gap. Buccal and musculoskeletal features were highly conserved within the group and regarding other Rhinella, and included four lingual papillae, nonkeratinized spurs, tripartite suprarostral cartilages, quadrato-orbital commissure, and in musculature, m. subarcualis rectus II–IV invading the branchial septum III and laryngeal muscles reduced or absent.

The Rhinella spinulosa group is a clade of toads that inhabit the Andes mountains from northern Ecuador to Patagonia. Its taxonomy was recently revised, and in its new arrangement comprises nine species, including Rhinella gallardoi, traditionally placed in a different intrageneric group. In this work we studied the larval external and internal morphology in this group, by describing for the first time tadpoles of R. achalensis, R. gallardoi, and R. vellardi, and then summarizing morphological data for R. altiperuviana, R. limensis, R. papillosa, R. spinulosa, and R. trifolium. Although we found no diagnostic larval features for the whole clade, two distinct morphs were identified. Most tadpoles were highly pigmented and slender, and their oral discs showed a long gap in the second labial tooth row; conversely, tadpoles of R. limensis and R. vellardi shared a globose body and a very short gap. Buccal and musculoskeletal features were highly conserved within the group and regarding other Rhinella, and included four lingual papillae, nonkeratinized spurs, tripartite suprarostral cartilages, quadrato-orbital commissure, and in musculature, m. subarcualis rectus II–IV invading the branchial septum III and laryngeal muscles reduced or absent.