Anguidae

Abstract: Reproductive mode data were extracted piecemeal from the literature and superimposed over currently accepted phylogenies to permit estimation of the minimum frequencies with which viviparity (live-bearing) has evolved in lizards, aswell as to facilitateanalysisoffactors hypothesizedto inlluencethis evolution. Viviparity has arisen on at least 45 separate occasions in the Sauria. Each ofthese origins is pinpointed phylogeneticallyas far as is now possible. Ofthese origins, 22 have occurred in the Scincidae, ten in the Iguanidae, five in the Anguidae, two each in the Lacertidae and Gekkonidae, and one each in the Chamaeleontidae, Xantusiidae, Agamidae, and Cordylidae. Further origins may be detected in the Scincidae, Iguanidae, and Diploglossa as phylogenetic relationships are elucidated. Over 19 % of the saurian species are live-bearing, and about 2/3 of the viviparous species are skinks. Most of the sub-generic saurian origins ofviviparity have occurred in cold climates, possibly as an adaptation to facilitate maternal thermoregulation of the developing embryos. Phylogenetic distributions of these origins are consistent with hypotheses that genetic sex-determination of the male-heterogametic type as weil as a tendency towards egg'retention preadapt a lineage for viviparity. Evolution of the live-bearing mode may be constrained by temperature-dependent sex determination, female heterogamety, and formation of highly calcified eggshells.

Abstract: Superimposition of reproductive mode data from the literature over phylogenetic classification systems reveals that viviparity (live-bearing reproduction) has evolved on at least 35 independent occasions among the Serpentes, once in the Amphisbaenia, and once in the Ichthyosauria. Of the ophidian origins of the live-bearing mode, at least fourteen have occurred in the Colubridae, twelve in the Viperidae, three in the Hydrophiidae (used in the sense of Smith et al., 1977), and one in each of the following groups: Boidae, Acrochordidae, Tropidophiidae, Uropeltidae, Typhlopidae, and Elapidae. Previous analysis has distinguished and defined 45 origins of viviparity among the lizards. Here, ten additional saurian origins are recognized on the basis of unpublished and recently published evidence, three in the Iguanidae, two in the Scincidae, and one in each of the following groups: Agamidae, Chamaeleontidae, Anguidae, Xenosauridae, and Anniellidae. As phylogenetic relationships are clarified, further origins seem likely to be detected, particularly in the Colubridae, Hydrophiidae, Scincidae, and Iguanidae. At present, however, at least 92 origins of viviparity can be recognized within the class Reptilia. Reptilian viviparity has arisen on multiple occasions in each of the six major biogeographic regions, with a majority of the origins having occurred in the Old World. Nearly 19% of the extant reptile species are probably live-bearers, including more than 20% of the snakes and over 19% of the lizards. About 71 % of the viviparous species belong to either the Scincidae, Colubridae, Viperidae, or Iguanidae. The discontinuous distribution of the origins of viviparity among the reptilian families supports the hypothesis that selective pressures, preadaptations, and constraints vary at high taxonomic levels.

Abstract: We present distribution data of all Anguidae, Scincidae, and Teiidae lizards known from the Brazilian Amazonia, totaling 29 species-level taxa, belonging to 14 genera. This represents 11 more species-level taxa than previously reported for these families in this area. Data were based on literature and 46,806 specimens deposited in three North American and eight Brazilian museums, including the main collections harboring Amazonian material. Most species (~55%) are endemic to Amazonia. Except for Ameiva ameiva , that is present in several environments and domains, non-endemic species are either associated with open dry (semideciduous) forest or open vegetation (savanna) enclaves in Amazonia, occupying similar environments outside Amazonia, gallery forests within the Cerrado, or present disjunct populations in the Atlantic Forest. As a whole, six taxa are widespread in Amazonia, four are restricted to eastern Amazonia, four to western Amazonia, three to southwestern Amazonia, one to northern Amazonia, and seven to the southern peripheral portion of Amazonia. Besides, two species present apparently more restricted, unique distributions. Only three species have a distribution that is congruent with one of the areas of endemism (AE) recognized for other organisms (birds and primates), of which two occur in AE Guiana and one in AE Inambari.

Abstract: The form and texture of the tongue has long been one of the major bases for the classification of lizards, as evidenced by such herpetological catalogues as de Rooij (1915) that base the “synopsis of families” principally on the tongue, and by the “-gjossa” names for higher groups of lizards in the older literature (e.g., Pachyglossa, Leptoglossa, Thecaglossa, Diploglossa, all used by Cope, 1900, but taken by him from earlier authors). I can find no case where a lizard was referred to a particular group on the basis of tongue structure but subsequently found, from other evidence, to be unrelated. On the other hand, in two cases families of lizards have been referred to higher groups against the evidence of the tongue, and subsequent study of the osteology has shown such reference to be in error: the Pygopodidae were referred by Camp (1923) to the same group as that containing Anguidae, Xenosauridae, Anniellidae, Helodermatidae, and Varani-dae, in spite of a very different tongue; but McDowell and Bogert (1954) and Underwood (1957) showed that the Pygopodidae are most closely related to the Gekkonidae, with which they agree in tongue structure as well as many other features.