The specialized inner ear labyrinth of worm-lizards (Amphisbaenia: Squamata).

High-resolution computed tomography (HRCT) has become a widely used tool for studying the inner ear morphology of vertebrates. Amphisbaenians are one of the most specialized groups of fossorial reptiles but are poorly understood relative to other squamate reptile. In this paper we survey the anatomy of the inner and middle ear of these fossorial reptiles using HRCT models and we describe qualitatively and quantitatively (using 3D morphometrics) the anatomy of the inner ear.

Compound osteoderms preserved in amber reveal the oldest known skink.

Scincidae is one of the most species-rich and cosmopolitan clades of squamate reptiles. Abundant disarticulated fossil material has also been attributed to this group, however, no complete pre-Cenozoic crown-scincid specimens have been found. A specimen in Burmite (99 MYA) is the first fossil that can be unambiguously referred to this clade.

The skull of the semi-aquatic neotropical lizard Echinosaura horrida (Gymnophthalmidae: Cercosaurinae) reveals new synapomorphies within Gymnophthalmoidea.

The rough teiid or water cork lizard (Echinosaura horrida) is a small reptile from Colombia and Ecuador placed in a genus that contains eight species and well-known phylogenetic relationships. Here we provide a detailed description and illustrations, bone by bone, of its skull, while we discussed its intraspecific variation by comparing high-resolution computed tomography data from two specimens and the variation within the genus by including previously published data from Echinosaura fischerorum. This allowed to propose putative diagnostic character states for Echinosaura horrida and synapomorphies for Echinosaura.

Toe pad morphology and adhesion in the miniaturized gecko, Chatogekko amazonicus (Gekkota: Sphaerodactylidae).

Chatogekko amazonicus is a miniaturized gecko from northern South America and is among the smallest of toe pad bearing lizards. The toe pads of C. amazonicus are miniscule, between 18% and 27% of the plantar surface area.

Comparative anatomy and evolution of the atlantoaxial complex in the fossorial lineage Amphisbaenia (Squamata: Lacertoidea).

The atlas and axis are the first two vertebrae from the cervical series; these two vertebrae are responsible for neck flexion, extension, and rotation movements, while providing insertion points for muscles and tendons. Amphisbaenia is a group of fossorial squamates known for having four distinctive head shapes, which are related to different excavation methods. However, little is known about the relationship between these different digging patterns and the anatomy and evolution of the atlantoaxial complex.

Variation in the cranial osteology of the amphisbaenian genus Zygaspis based on high-resolution x-ray computed tomography.

Amphisbaenians are a specialized fossorial group of reptiles, having developed head-first burrowing, a specialized skull architecture, and an elongated body. This group is generally small-bodied, with some species possessing skulls only a few millimeters long. In this study, we used high-resolution x-ray computed tomography to compare the skulls of 15 specimens from seven of the eight species in the amphisbaenian genus Zygaspis (Zygaspis dolichomenta, Zygaspis ferox, Zygaspis quadrifrons, Zygaspis kafuensis, Zygaspis nigra, Zygaspis vandami, and Zygaspis violacea).

Reappraising the evolutionary history of the largest known gecko, the presumably extinct Hoplodactylus delcourti, via high-throughput sequencing of archival DNA.

Hoplodactylus delcourti is a presumably extinct species of diplodactylid gecko known only from a single specimen of unknown provenance. It is by far the largest known gekkotan, approximately 50% longer than the next largest-known species. It has been considered a member of the New Zealand endemic genus Hoplodactylus based on external morphological features including shared toe pad structure.

A new gecko from the earliest Eocene of Dormaal, Belgium: a thermophilic element of the 'greenhouse world'.

We here describe a new gekkotan lizard from the earliest Eocene (MP 7) of the Dormaal locality in Belgium, from the time of the warmest global climates of the past 66 million years (Myr). This new taxon, with an age of 56 Myr, together with indeterminate gekkotan material reported from Silveirinha (Portugal, MP 7) represent the oldest Cenozoic gekkotans known from Europe. Today gekkotan lizards are distributed worldwide in mainly warm temperate to tropical areas and the new gecko from Dormaal represents a thermophilic faunal element.

Bridging the Research Gap between Live Collections in Zoos and Preserved Collections in Natural History Museums.

Zoos and natural history museums are both collections-based institutions with important missions in biodiversity research and education. Animals in zoos are a repository and living record of the world's biodiversity, whereas natural history museums are a permanent historical record of snapshots of biodiversity in time. Surprisingly, despite significant overlap in institutional missions, formal partnerships between these institution types are infrequent.

A new Early Cretaceous lizard in Myanmar amber with exceptionally preserved integument.

We here report on a well-preserved juvenile lizard specimen in Albian amber (ca. 110 mya) from the Hkamti site (Myanmar). This new taxon is represented by an articulated skull and the anterior portion of the trunk, including the pectoral girdle and forelimbs.

Unveiling the elusive: X-rays bring scolecophidian snakes out of the dark.

Scolecophidian snakes have long posed challenges for scholars interested in elucidating their anatomy. The importance, and relative paucity, of high-quality anatomical data pertaining to scolecophidians was brought into sharp focus in the late 20 century as part of a controversy over the phylogeny and ecological origin of snakes. The basal position of scolecophidians in the phylogeny of snakes makes their anatomy, behavior, ecology, and evolution especially important for such considerations.

The status of the anomalepidid snake Liotyphlops albirostris and the revalidation of three taxa based on morphology and ecological niche models.

Liotyphlops is a genus of blindsnakes distributed in Central and South America. We reviewed specimens of Liotyphlops albirostris along its current distribution range and, based on morphological data and ecological niche modeling analyses, we restrict the geographical range of L. albirostris and validate three previously described species.

Blind snakes beneath the surface: Continuing the legacy of Richard Thomas.

Blind snakes (Scolecophidia) are small-bodied, enigmatic burrowing reptiles with members found on all continents except Antarctica. This Special Issue on blind snakes honors and advances the foundational studies by a remarkable anatomist, Richard Thomas. Richard is currently one of the living herpetologists to have described the greatest number of herpetofauna species, including many blind snake taxa.

Ecomorphometric Analysis of Diversity in Cranial Shape of Pygopodid Geckos.

Pygopodids are elongate, functionally limbless geckos found throughout Australia. The clade presents low taxonomic diversity (∼45 spp.), but a variety of cranial morphologies, habitat use, and locomotor abilities that vary between and within genera.

Comparative anatomy of the middle ear in some lizard species with comments on the evolutionary changes within Squamata.

The skeleton of the middle ear of lizards is composed of three anatomical elements: columella, extracolumella, and tympanic membrane, with some exceptions that show modifications of this anatomy. The main function of the middle ear is transforming sound waves into vibrations and transmitting these to the inner ear. Most middle ear studies mainly focus on its functional aspects, while few describe the anatomy in detail.

The herpetological contributions of Richard Thomas.

John Paul Richard Thomas is among the living herpetologists to have described the greatest number of new species of amphibians and reptiles, and his contributions to the herpetology of the West Indies, particularly the Greater Antilles, have been exceptional. His academic career followed an unusual path, having established a strong reputation and described 50 new taxa prior to beginning his doctoral studies. His career was strongly influenced by Albert Schwartz and later was characterized by extensive and fruitful collaboration with S.

Underground Down Under: Skull anatomy of the southern blind snake Anilios australis Gray, 1845 (Typhlopidae: Serpentes: Squamata).

The cranial anatomy of blindsnakes has been markedly understudied, with the small size and relative rarity of encountering these subterranean reptiles being significant limiting factors. In this article, we re-visit the skull anatomy of the Australian southern blind snake Anilios australis Gray, 1845 using microCT data, and produce the first complete atlas for the cranial anatomy of a representative of this speciose typhlopid genus. The skull is formed by 18 paired and four unpaired elements.

Unusual morphology in the mid-Cretaceous lizard Oculudentavis.

Oculudentavis khaungraae was described based on a tiny skull trapped in amber. The slender tapering rostrum with retracted narial openings, large eyes, and short vaulted braincase led to its identification as the smallest avian dinosaur on record, comparable to the smallest living hummingbirds. Despite its bird-like appearance, Oculudentavis showed several features inconsistent with its original phylogenetic placement.

A biographical account of John Paul Richard Thomas, the man who leaves no stone unturned.

This biographical account summarizes the professional career and scientific contributions of John Paul Richard Thomas, a contemporary leading figure in the systematics of West Indian amphibians and non-avian reptiles, especially of blind snakes of the families Typhlopidae and Leptotyphlopidae. Since his first expedition to the West Indies in 1957, Richard's vast field experience (including three trips to Peru between 1968 and 1974), impressive collecting skills, and remarkable ability to detect phenotypic variation among natural populations have resulted in the description of more than 70 species of snakes (24 typhlopids, 4 leptotyphlopids), lizards, and frogs in 16 genera and 11 taxonomic families. Richard joined the faculty of the Department of Biology, University of Puerto Rico, Río Piedras, in 1976 and ever since his efforts significantly advanced organismal biology research at the institution.

Extended diagnosis of the type species of Pseudogonatodes Ruthven 1915 (Gekkota: Sphaerodactylidae).

Pseudogonatodes furvus is an endemic gecko from the region of the Sierra Nevada de Santa Marta, an isolated massif located in the continental Caribbean region of Colombia. Pseudogonatodes furvus is the type species of the genus, and its morphology and natural history remain poorly known. This lizard was described based on two specimens.

Enigmatic amphibians in mid-Cretaceous amber were chameleon-like ballistic feeders.

Albanerpetontids are tiny, enigmatic fossil amphibians with a distinctive suite of characteristics, including scales and specialized jaw and neck joints. Here we describe a new genus and species of albanerpetontid, represented by fully articulated and three-dimensional specimens preserved in amber. These specimens preserve skeletal and soft tissues, including an elongated median hyoid element, the tip of which remains embedded in a distal tongue pad.