Squamate Assemblage Research Articles

Herpetofauna diversity from late Holocene wetlands of northeastern Argentina

AbstractThe palaeofauna of the Quaternary is mostly known from the mammals' record, while the herpetofauna is less represented. In the same way, in northeastern Argentina reptile fossils records are scarce, usually represented by preliminary communications. This paper focuses on the study of herpetofauna remains from the Isla El Disparito archaeological site. The faunal materials collected at the site revealed an increase in taxonomic diversity related to the Quaternary herpetofauna in the IED site, with over 50% of the bone remains represented by anurans and at least six recognized squamates taxa. The purpose of this study is to properly identify these new records of herpetofauna remains from northeastern Argentina during the Holocene as well as to provide a dichotomous key of postcranial remains for identifying extant squamates taxa in other Quaternary sites from Argentina. The identified squamate assemblage includes the lizard Ophiodes sp., the snake families Typhlopidae, Dipsadidae, Viperidae and undetermined colubroids, along with anuran bone remains (Anura indet. and ?Hylidae). Additionally, the findings contribute to a better understanding of the herpetological assemblage in Argentina, providing insights into the composition of South American squamates during the Quaternary.

Climate and habitat niche diversification in a southwest European squamate assemblage

Climate and habitat niche diversification in a southwest European squamate assemblage

The anurans and squamates assemblage from Final Natufian Eynan (Ain Mallaha, Israel) with an emphasis on snake-human interactions.

During the Natufian period, more than 12,000 years ago, Eynan (Ain Mallaha) was an important human settlement in the Hula Valley, Israel. This study concentrates on the anuran and squamate assemblage from the ultimate stage of the Natufian period at the site, the Final Natufian. Over five thousand bones assigned to at least sixteen taxa were studied from a sampled segment of the excavated open-air site. Relative species abundance, spatial distribution, taphonomic observations and ecological considerations all pointed to the conclusion that the inhabitants of Eynan intensively exploited three large “colubrine” snakes species: the Large Whip Snake (Dolichophis jugularis), the Eastern Montpellier Snake (Malpolon insignitus) and an Eastern Four-lined Ratsnake (Elaphe cf. sauromates). These snakes were the most desired and were intensively gathered, while other snakes and lizards could have been opportunistically collected when encountered. We raise questions about whether the large “colubrines” exploitation should be interpreted as additional evidence of increasing diet breadth. We suggest challenging this line of reasoning and offer possible alternative motives.

Early Pleistocene amphibians and squamates from Copăceni (Dacian Basin, southern Romania)

This paper describes an Early Pleistocene amphibian and squamate assemblage from the Dacian Basin, southern Romania. The fossil sample allows for the identification of a moderately diverse assemblage, which includes representatives of 13 genera of the families Salamandridae (Lissotriton vulgaris, Triturus sp.), Bombinatoridae (Bombina sp.), Hylidae (Hyla aff. Hyla arborea), Bufonidae (Bufo bufo), Pelobatidae (Pelobates syriacus), Ranidae (Ranidae indet., Pelophylax sp., Rana ?temporaria, Rana sp.), Lacertidae (Lacertidae indet.), Anguidae (Pseudopus sp.), Natricidae (Natrix natrix), and Colubridae (Coronella austriaca, Zamenis longissimus). The taxonomic composition of the Early Pleistocene amphibian and squamate assemblage from Copăceni is similar to the one reported from other Romanian sites of the same age, and also to that of Recent Romanian herpetofaunas. The amphibian and squamate assemblage from Copăceni supports the existence of a permanent freshwater body, of neighbouring forests or shrubberies, and thick soil, in an Early Pleistocene climate that was warmer than the present one.

Early Miocene squamate assemblage from the Mokrá-Western Quarry (Czech Republic) and its palaeobiogeographical and palaeoenvironmental implications

Two fossiliferous karstic fissures from the Mokrá-Western Quarry, MWQ (1/2001 Turtle Joint; 2/2003 Reptile Joint) provided a diverse vertebrate fauna from the early Miocene (Burdigalian, MN 4) including squamates. The rather warm climatic conditions during the Miocene Thermal Maximum (17.8-17.7 Ma) enabled dispersal of thermophilic lizards and snakes throughout Central Europe. In total, ten major clades have been identified in MWQ localities, including: Lacertidae (Lacertidae indet., Lacertidae tooth morphotype 1 and 2); Amphisbaenia (Amphisbaenia indet.); ? Scincoidea (? Scincoidea indet.); Anguidae (Pseudopus laurillardi (Lartet, 1851), Pseudopus sp., Ophisaurus sp., and Anguinae indet.); Varanidae (Varanus mokrensisIvanov, Klembara, Ruta & Böhme, 2018); Boidae (Bavarioboa cf. hermiSzyndlar & Schleich, 1993); Pythonidae (Python sp.); Colubridae (Colubridae gen. et sp. indet., Coluber [s.l.] sp., and “Colubrinae” indet., type 1), Natricidae (Natrix sp. and “Natricinae” indet.); Viperidae (Viperinae [‘Oriental vipers' group], Vipera sp. [‘European vipers' group]); and Elapidae (Elapidae gen. et sp. indet.). Python sp. from the MWQ represents the first known occurrence of this most thermophilic Neogene squamate taxon within the area of Central Paratethys and we assume that MAT did not fall below 18-19 °C in the vicinity of this locality during the late Burdigalian stage. These humid subtropical to paratropical climatic conditions, also documented by several full-aquatic and semi-aquatic amphibians and reptiles, were suitable for the occurrence of other thermophilic lizard and snake taxa reported from MWQ, including Varanus mokrensis, Pseudopus laurillardi, Bavarioboa, large Elapidae and ‘Oriental vipers'.

New taxa among a remarkably diverse assemblage of fossil squamates from the Aguja Formation (lower Campanian) of West Texas

A diverse microfauna from the lower shale of the Aguja Formation of West Texas records a rare, early Campanian assemblage of fossil squamates from North America. This assemblage is comprised of scincomorph, anguimorph, and ophidian taxa and is the most inclusive of its kind thus far described from the southern faunal province of Laramidia. Among numerous taxa described herein, three (Hypostylos lehmani gen. et sp. nov., Bothriagenys flectomendax sp. nov., and Hydrargysaurus gladius gen. et sp. nov) pertain to new scincomorphs which dominate the assemblage; however, subordinate anguimorphs are also well-represented. Snakes are represented by a single taxon, aff. Coniophis; a species seemingly ubiquitous throughout most Campanian strata in the southern Western Interior. Comparison among squamate assemblages from similar coastal facies in the upper shale of the Aguja Formation as well as the paracontemporaneous Wahweap and Kaiparowits formations of southern Utah reveals patterns of biogeographic segregation among some lizard species and the presence of two distinct communities. These two ‘southern’ squamate faunas are likely the result of variables involving climate and eustacy which facilitated diversity as well as the development of sub-provincial quarters of endemism during early-middle Campanian time.

Habitat Assessment of the Broad-Headed Skink (Plestiodon laticeps) and the Associated Squamate Community in Eastern Kansas

During the summers of 2015-2017, we performed standardized surveys across the known range of the Broad-headed Skink in eastern Kansas. We used a combination of drift fence arrays with funnel traps and visual encounter surveys (VES) to collect occurrence data on the Broad-headed Skink. A Canonical Correspondence Analysis (CCA) was used to determine which habitat variables explained the variation observed in the squamate assemblage. The position of the Broad-headed Skink was explained by average log length and overstory tree size. A secondary analysis implies the Broad-headed Skink is also associated with presence of Black Walnut (Juglans nigra). A logistic regression was used to determine which habitat variables were significant in predicting presence of the Broad-headed Skink. The variables from the most successful model included average log length, overstory tree size, understory tree dispersion, and overstory tree dispersion. These habitat attributes suggest the Broad-headed Skink prefers mature patches of forest, and habitat structure rather than tree species composition is more useful in predicting Broad-headed Skink presence.

Oldest co-occurrence of Varanus and Python from Africa-first record of squamates from the early Miocene of Moghra Formation, Western Desert, Egypt.

Lizard and snake remains from the early Miocene (Burdigalian) of the Moghra Formation, Egypt, are described herein. This material comprises the first fossil remains of squamates recovered from the otherwise rich and well known vertebrate assemblage of Moghra. The material pertains to two different genera, the varanid lizard Varanus and the pythonid snake Python and adds to the so far rather poorly known squamate fossil record from Africa. On the basis of the new remains, Moghra marks the oldest so far described co-occurrence of Varanus and Python in the African continent. The close sympatry of these two genera in the African fossil record is thoroughly analyzed and discussed, a co-existence, which is still widespread in the extant herpetofauna of the continent. Situated rather close to the so called “Levantine Corridor” and dated at the Burdigalian, practically when Afro-Arabia collided with Eurasia, the Moghra squamate assemblage offers the potential of important insights in the biogeography and dispersal events of vertebrate groups during the early Miocene.

New fossil lizard specimens from a poorly-known squamate assemblage in the Upper Cretaceous (Campanian) San Juan Basin, New Mexico, USA

Recent collection efforts in the upper Campanian (∼76-73.5 Ma) Fruitland and Kirtland formations of northwestern New Mexico have significantly increased the taxonomic diversity of lizards in this historically poorly understood squamate assemblage. New lizard specimens from the “Hunter Wash Local Fauna” of the upper Fruitland and lower Kirtland formations include: (1) new specimens referable to Chamopsiidae; (2) new material belonging to Scincomorpha, (3) new material belonging to Anguidae; and (4) the first reported predatory lizard (Platynota) material from the Campanian of New Mexico. The increase in lizard diversity in the “Hunter Wash Local Fauna” expands our understanding of Late Cretaceous squamate taxonomy, distribution, and diversity in the Western Interior of North America (Laramidia). Collectively, the described specimens represent family-level diversity similar to that seen in other Campanian foreland basin deposits of the Western Interior, such as the mid-paleolatitude Kaiparowits Formation of southern Utah, the higher paleolatitude Dinosaur Park Formation of southern Alberta, and the lower paleolatitude Aguja Formation of southwestern Texas. The lizards of the “Hunter Wash Local Fauna” represent crucial mid-paleolatitude data from a coastal plain depositional setting in Laramidia—allowing for comparisons to more well-studied assemblages at different latitudes and in different depositional settings.

Camera-traps are a cost-effective method for surveying terrestrial squamates: A comparison with artificial refuges and pitfall traps

IntroductionFundamental data on the distributions, diversity, and threat status of terrestrial snakes and lizards (hereafter squamates) is limited. This is due to the cryptic nature of species in this faunal group, and to limitations in the effectiveness of the survey methods used to detect these species. Camera-traps are a useful tool for detecting numerous vertebrate species, yet their use for detecting squamates has been limited. Here, we apply recent methodological advancements in camera-trapping and assessed the utility of camera-traps for inventorying a squamate assemblage by comparing camera-trapping survey results with two widely used labour-intensive methods: artificial refuges and pitfall traps.MethodsWe conducted a 74-day survey using camera-traps and, concurrently, four by four-day surveys using labour-intensive methods. Given the duration and three detection methods, we compared seven variants of survey protocol, including using each method alone or all methods simultaneously. We compared both the effectiveness and cost-effectiveness of each survey protocol by estimating the number of species detected at the transect level, and by calculating the costs of conducting those surveys.ResultsWe found the camera-trapping survey was most cost-effective, costing 687 AUD (CI 534–912) per squamate species detected, compared with the 2975 AUD (CI 2103–4486) per squamate species detected with the labour-intensive methods. Using all methods together was less cost-effective than using camera-traps alone. Additionally, there was a 99% probability that camera-traps would detect more species per transect than the labour-intensive methods examined.Discussion & conclusionBy focusing the analysis at the level of the survey, rather than the level of the device, camera-traps are both a more effective and cost-effective technique for surveying terrestrial squamates. Where circumstances are appropriate, those wildlife researchers and managers currently using camera-traps for non-squamate surveys, can adopt the methods presented to incorporate squamate surveys with little upfront cost. Additionally, researchers currently using traditional techniques can be confident that switching to camera-traps will likely yield improved results. Still, camera-traps are not a panacea and careful consideration into the benefits and usefulness of these techniques in individual circumstances is required.

Evaluating the Ecology of Tantilla relicta in Florida Pine–Wiregrass Sandhills Using Multi-Season Occupancy Models

Occupancy modeling may be the most effective tool for studying the occurrence of secretive fossorial squamates. Our objective was to use occupancy models to test whether Florida Crowned Snakes (Tantilla relicta) are a suitable model species for other, more-secretive fossorial squamates. Tantilla relicta are easier to study than other fossorial squamates and likely respond to habitat management (e.g., fire frequency) similarly to these harder-to-study species of concern. We sampled T. relicta using 24 groups of drift fences in longleaf pine–wiregrass sandhills, Ocala National Forest, Florida, USA to assess how habitat characteristics and weather influenced their occupancy, detection, colonization, and extinction rates. We predicted that temperature, rainfall, substrate composition, and prescribed burn history would influence T. relicta occupancy, detection, and movement in variable directions. The best-supported multiseason occupancy model included 1) initial occupancy influenced by time since last burn, 2) extinction and colonization as random processes, and 3) detection influenced by percent leaf litter and rainfall. Tantilla relicta were most likely to occupy recently burned sites and were most easily detected during dry periods and at sites with low leaf litter cover. Our results are consistent with research suggesting that short-return prescribed fires benefit many reptile species in central Florida's xeric longleaf pine–wiregrass forests. Further, our results provide modest evidence that T. relicta are suitable model organisms for studying fossorial squamate assemblages.

Species composition, abundance and diet of a squamate assemblage from the Carnaval stream headwaters (Buenos Aires, Argentina)

The present work summarizes 10 years of field observations of an exurban squamate assemblage occupying a 1200 ha patch in the suburbs of La Plata City (Los Portenos, Buenos Aires, Argentina). Crossed by two streams (Martin and Carnaval), the area is characterized by intensive horticulture and floriculture, poultry and pig farming, exhibits a low housing density (1 house/ha), and the roads are largely unpaved. This area is under stress due to continuous expansion of the neighboring city in detriment of rural areas, determining a stressing environmental scenario. Field data were complemented and contextualized with museum records of the squamates present in the area and in neighboring departments of La Plata. The field-based species list of squamates from Los Portenos comprises one amphisbaenian (Amphisbaena darwinii = 26 specimens), five snakes (Paraphimophis rustica = 24, Xenodon dorbignyi = 6, Erythrolamprus poecilogyrus = 3, Erythrolamprus semiaureus = 2, Lygophis anomalus = 1), and one lizard (Salvator merianae = 11). The number of species of squamates in Los Portenos was higher than the expected compared with the species from surrounding areas. Fossorial, nocturnal and generalist species were the most abundant in Los Portenos. These urban adapter species lack dietary constraints and their living habits minimize the encounters with humans, who commonly kill them.

The first Gondwanan borioteiioid lizard and the mid-Cretaceous dispersal event between North America and Africa

Borioteiioidea are an enigmatic group of Cretaceous lizards widely distributed in northern continents (Laurasia). Here, we describe the first borioteiioid lizard from Gondwana, represented by a new species of the polyglyphanodontine genus Bicuspidon, B. hogreli sp. nov., from the Cenomanian Kem Kem beds of Morocco. The discovery of Bicuspidon hogreli sp. nov., which is one of the oldest known member of Polyglyphanodontini, challenges previous assumptions on the center of origin and dispersal of the group. In addition, the known distribution of Bicuspidon (Cenomanian of Utah and Morocco, and Santonian-Maastrichtian of eastern Europe) suggests a complex palaeobiogeographical history for the genus. The existence of a terrestrial dispersal route persisting during the whole Early Cretaceous between North America and Africa is hypothesized to explain some similarities observed between the Cenomanian squamate assemblages of these two continents. Alternatively, dispersal between the two landmasses may have occurred by transatlantic rafting. During the Cenomanian-Santonian interval, Bicuspidon colonized the European archipelago probably from North Africa, like many "Eurogondwanan" taxa.

A frontier in the use of camera traps: surveying terrestrial squamate assemblages

AbstractThere is an urgent need to improve methods for surveying snakes and lizards (squamates). Currently, fundamental data gaps exist about squamate distributions and abundance in numerous regions. Traditional squamate survey methods are useful, but they are also resource and labour intensive. In recent decades, camera traps have provided researchers an effective, cost‐efficient and minimally invasive survey tool; albeit primarily for birds, mammals and fish. The use of camera traps for reptiles generally, and squamates specifically, has been limited. Yet, recent developments in camera trapping methodology demonstrate how they could be used to survey a squamate assemblage. Although further research is required, these developments are encouraging. Thus, surveying squamates with camera traps is a primary frontier in camera trapping.

The combined influence of riverine barriers and flooding gradients on biogeographical patterns for amphibians and squamates in south‐eastern Amazonia

AbstractAimOur aim was to investigate how the distance to water (flooding gradients) and riverine barriers (Tapajós and Jamanxim rivers) influence the distributional patterns of amphibian and squamate assemblages in the middle Tapajós River region, south‐eastern Amazonia. We also considered the planned hydroelectric dams on both rivers in reviewing the possible impacts of these factors on the amphibian and squamate assemblages.LocationMiddle Tapajós River system, south‐eastern Amazonia.MethodsWe conducted diurnal and nocturnal surveys combining pitfall traps and active searches along both banks of the Tapajós and Jamanxim rivers. We identified specimens using an integrative morphological, acoustic, ecological and molecular approach and evaluated the influence of riverine barriers and distance to water using uni‐ and multivariate ordinations, regressions and ANOVA.ResultsWe found changes in species composition for both groups along the flooding gradient and differential riverine barrier effects. The rivers restricted the distribution of 33% of the amphibian species and 8% of the squamates. For amphibians, the main distributional barrier was the Tapajós River, while for squamates both rivers were of similar importance. The assemblages most affected by riverine barriers were non‐riparian amphibians and squamates, as well as riparian amphibians associated with small streams. The functional groups most affected were small, diurnal terrestrial amphibians and small–medium, diurnal partly tree‐dwelling squamates.Main conclusionsThe Tapajós River is a distributional boundary for lineages centred in western and eastern Amazonia. The fact that many taxa occur on both banks suggests that the Tapajós is a recent or semi‐permeable barrier, while the Jamanxim is an even more recent or weaker barrier. Anthropogenic activities that affect water level, flooding cycles and river flow may influence these natural patterns and cause changes to the equilibrium of the riverine barrier effect. Studies seeking to identify these influences should focus on the most affected functional groups.

A new teiid lizard from the Late Cretaceous of the Haţeg Basin, Romania and its phylogenetic and palaeobiogeographical relationships

A new lizard genus and species is described based on a three-dimensionally preserved partial skull and associated lower jaws from the Pui Islaz locality (Late Cretaceous, early Maastrichtian) in the Haţeg Basin, western Romania. Barbatteius vremiri gen. et sp. nov. is diagnosed by a unique combination of symplesiomorphies and synapomorphies. A nested set of synapomorphies support assigning Barbatteius to Teiidae as the first unambiguous Late Cretaceous record of this family from Laurasia. Barbatteius differs from other teiids by having more extensive osteodermal sculpture on the skull roof and suspensorium, and by a pentagonal occipital osteoscute exhibiting more or less parallel lateral margins. Barbatteius is a large-bodied lizard, estimated to be up to 800 mm in total length. It has weakly heterodont dentition, but without enlarged posterior crushing teeth, suggesting that it fed on arthropods, small vertebrates and plants. The mix of taxa with affinities to Euramerica (paramacellodid and borioteiioid lizards) and Gondwana (madtsoiid snakes and the teiid Barbatteius) currently known for the Maastrichtian squamate assemblage from Haţeg Basin supports the growing realization that ‘Haţeg Island’ has a complex palaeobiogeographical history.http://zoobank.org/urn:lsid:zoobank.org:pub:75C2D80F-8DDB-4FB2-9844-1552D626F63D

New Records of Squamates from the Upper Miocene of South America

Abstract The Cerro Azul Formation of Argentina has yielded one of the highest diversities of squamate reptiles for the upper Miocene of South America including tupinambine teiids (Tupinambis sp.), “colubrids,” and viperids. Here, we describe new remains of Tupinambis sp. and “Colubridae” from this Formation as well as the first records of teiine teiids and boid snakes. The teiine represents the oldest record of this subfamily in South America. The squamate assemblage of the Cerro Azul Formation is consistent with the mammalian fauna in supporting the interpretation of a Chacoan-type palaeoenvironment for the upper Miocene of Central Argentina.

“Mesozoic and Cenozoic lissamphibian and squamate assemblages of Laurasia”—introduction to the special issue

Lissamphibia (frogs, salamanders, caecilians, and albanerpetontids) and Squamata (lizards, snakes, and amphisbaenians) have been persistent components of many non-marine ecosystems on Earth since the early part of the Mesozoic. Both clades have extant and fossil occurrences on every modern continent, except Antarctica. The three Northern Hemisphere continents of Europe, Asia, and North America, which owe their origins largely to the mid-Mesozoic break-up of the former supercontinent Laurasia, have yielded the lion’s share of fossils for both groups. Consequently, the Laurasian fossil record has been critical for shaping our ideas about the diversities and evolutionary histories of lissamphibians and squamates. The earliest collections and descriptions of fossil lissamphibians and squamates from the former Laurasian continents date back to the early 1800s in Europe, followed decades later by discoveries in North America (western USA) in the 1870s and in Asia (Mongolia) in the 1920s (e.g. see historical summaries by Caldwell 2007; Estes 1981, 1983; Sanchiz 1998). Until the middle part of the twentieth century, descriptive work on fossil lissamphibians and squamates tended to focus on articulated skeletons, such as those of Oligo–Miocene anurans from Central Europe (e.g. von Meyer 1860; Wolterstorff 1885) and of Early Cretaceous lizards and of what is now regarded as an albanerpetontid from Italy (e.g. Costa 1864). Although generally of less interest, isolated and articulated bones recovered by quarrying, surface collecting, or dry screening also merited some attention; to cite two examples, a mandible from the late Oligocene of France became the holotype of the earliest named fossil lizard, Dracaenosaurus croizeti Gervais 1848–1852, and the dozen or so fossil lissamphibians and squamates named by Cope and Marsh in the late 1800s from the Late Jurassic and latest Cretaceous of the western USA were described on isolated bones (e.g. Cope 1876; Marsh 1872, 1887, 1892). Even after more than a century of work, by the middle part of the twentieth century our understanding of fossil lissamphibians and squamates was limited to a small number of taxa known mostly from Europe and western North America, and largely from the Cenozoic. Aside from scattered and intriguing occurrences, little was known about either group from that era and much of the entire Asian fossil record remained a blank. Two developments in the latter part of the twentieth century dramatically improved our access to the lissamphibian and squamate fossil records. The first development was the widespread adoption in the 1950s of screen washing (McKenna 1962) as a method to bulk process fossiliferous matrix by washing it through fine screens in order to recover small bones, teeth, and scales preserved in the rock. Screen washing was pioneered by palaeomammalogists and is still widely used by them as a way to recover mammalian teeth and jaws, particularly from fossil localities that are not suitable for hand quarrying and as a way to salvage fossils from the rubble left behind after quarrying. The “by-catch” of non-mammalian fossils caught in the screens often includes jaws, vertebrae, and other bones of lissamphibians and squamates. Estes’ (1964) monograph, “Fossil vertebrates from the Late Cretaceous Lance Formation, eastern Wyoming” demonstrated that screen washing could provide large enough samples to This article is a contribution to the special issue Mesozoic and Cenozoic lissamphibian and squamate assemblages of Laurasia

Lizards and snakes of the Terlingua Local Fauna (late Campanian), Aguja Formation, Texas, with comments on the distribution of paracontemporaneous squamates throughout the Western Interior of North America

ABSTRACT The late Campanian–aged (= Judithian) squamates from the Terlingua Local Fauna of the Aguja Formation, southern Texas, includes four scincomorphans: a new taxon (Catactegenys solaster, gen. et sp. nov.), referable to Xantusiidae, that has massive teeth and tooth crown morphology similar to that of contogeniid lizards; an indeterminate scincomorphan (Apsgnathus triptodon, gen et sp. nov.) with robust teeth; and two unnamed scincomorphan morphotypes. Anguimorphans in the fauna include Odaxosaurus piger, cf. Parasaniwa wyomingensis, and a likely xenosaur. Ophidian jaw fragments confirm the presence of a snake in the fauna. The Aguja squamate assemblage is one of the most southerly of a series of paracontemporaneous squamate faunas extending from central Alberta to northern Mexico. Comparison of these faunas reveals that, although two taxa are endemic to the Aguja Formation, others show some latitudinal trends. Odaxosaurus and Parasaniwa are present in all well-sampled faunas from Alberta to Texas. The mammal-like Peneteius and snakes are found only in faunas from southern Utah to Mexico. Chamopsiids are only present from Alberta to New Mexico. The sole representatives of Contogeniidae and Xantusiidae are restricted to southern Utah and southern Texas, respectively. These hypotheses of distributional patterns must continue to be tested through ongoing investigations of all of the relevant faunas from the late Campanian of the Western Interior. SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP

Lizards and amphisbaenians (Reptilia, Squamata) from the late Eocene of Sossís (Catalonia, Spain)

A new diverse late Eocene lizard and amphisbaenian assemblage from the classical mammal locality of Sossis (Catalonia, Spain) is described. It represents the first Paleogene lizard assemblage from Spain and the first late Eocene lizard locality from the Iberian Peninsula. The family-level composition of the assemblage replicates that of other contemporaneous European localities, with the presence of iguanians, geckos, lacertids, scincids, cordyliforms, amphisbaenians, anguines, and glyptosaurines. Many of these families still occur in Catalonia, but the presence of thermophilic taxa like iguanians and cordyliforms are indicative of warmer conditions during the Eocene. The closest faunal match is with the contemporaneous French localities of the Phosphorites du Quercy. Sossis and other newly recovered Paleogene Spanish squamate assemblages have the potential to contribute to an understanding of patterns of faunal interchange between different Paleogene bioprovinces, complementing existing data on mammals. © Palaeontological Association March 2013.