Authors: Mariano Hernandez, Nicole Macameyer, J. Carlos Rando, Alfredo Valido And Manuel Nogales

Authors: Chris P. Gleed-owen

Authors: Wolfgang Wüster , José Luis Yrausquin And Abraham Mijares-urrutia

Abstract: We describe a new species of snake of the genus Drymarchon from Falcón State north-western Venezuela. The distinctive nature of this species, compared to the two other South American mainland taxa of Drymarchon, is supported by principal components analysis of scalation and colour pattern characters. The taxa corais and melanurus, hitherto considered conspecific, are found to be highly distinct, but homogeneous throughout their considerable ranges; consequently, we consider melanurus to be a full species, separate from Drymarchon corais.

Keywords: Drymarchon, taxonomy, systematics, new species, multivariate morphometrics, South America

Authors: Christopher H. Shewchuk And James D. Austin

Abstract: Dietary habits of the racer, Coluber constrictor mormon, were studied based on stomach and faecal contents from 26 road killed specimens and 297 live animals collected in the field during 1992-1994 in southern British Columbia, Canada. Thirty percent of the specimens examined contained gut contents. Coluber constrictor mormon feeds mainly on insects (91% of prey; Acnd1dae > Gryllidae > Tettigoniidae > Gryllacrididae) and occasionally rodents (7.5% of prey), as well as frogs and snakes (both < I %). There were proportionally more vertebrates in the diets during the early part of the season (April - May). Diet was related to individual attributes, such as size or sex of the snake. Thus, larger individuals - primarily females - were more. likely to . feed on vertebrates, although insects were not absent from the diet of larger individuals. Diet composition (mammals vs. insects only) did not depend upon the method of sampling snakes. This study adds to the growing number of dietary studies on Coluber constrictor that continue to provide insights into the evolutionary ecology of this widespread but poorly-known species.

Keywords: Coluber constrictor, feeding ecology, British Columbia, Canada, diet, food habits

Authors: D. J. Harris And P. Sá-sousa

Abstract: Wall lizirds (Podarcis) are the dominant reptile group across most of southern Europe. Their taxonomy is complex because most species exhibit substantial intraspecific morphological polymorphisms. We have estimated the phylogeny of the particularly diverse western Iberian forms using partial cytochrome oxidase and cytochrome b mitochondrial DNA sequence data and have compared this against morphological variation. Of the two currently recognized species in the area-.Podarcis hispanica and P. bocagei -neither is monophyletic, and extremely high genetic d1vers1ty between newly identified forms (up to 1 5% cytochrome b divergences) indicates that both are species complexes. Podarcis b. bocagei is genetically distinct from P. (b.) carbonelli which appears to be a separate species using both mtDNA and protein electrophoretic data. The insular form previously assigned to P. b. berlengensis, and sometimes argued to deserve species status is not genetically distinct from P. (b.) carbonelli using the mtDNA sequences. P. hispanica can be separated into at least four highly divergent groups, two in western Iberia, one in eastern Iberia and one in North Africa.

Keywords: phylogeny, cytochrome b, cytochrome oxidase, morphology, Iberian lizards

Authors: Fernando Lobo

Abstract: The lizard genus Liolaemus includes over 160 species of which almost h lf are in the chiliensis group. Although some researchers have attempted to define smaller species groups within this large clade, the relationships among the taxa within the group as a whole remain enigmatic. The objectives of this study were to (1) identify characters that will be useful for present and future phylogenetic studies of this group, and (2) generate preliminary phylogenetic hypotheses for taxa within this large clade of lizards. I examined more than 800 specimens of 73 taxa belonging to the chiliensis group from which I identified 55 phylogenetically informative morphological characters. Additional characters (6) were derived from published and unpublished data on chromosomes, life history, and ecology. Four species considered basal for the genus were taken as outgoups. A tree-building program (PAUP 4.0b2) recovered three trees of length 1 1 . 516 (Retention index: 0.59). Differences found among these topologies were restricted to the relationships of species of the elongatus group, in which monophyly was recovered in only one tree . . Results from PAUP's analysis support the monophyly of several previously proposed species groups: alticolor, altissimus, gravenhorstii, hellmichi, kriegi, leopardinus, monlicola, nigromaculatus, nigroviridis, pielus and tenuis. Interestingly, most of the groups indicated above are endemic to areas that have recently been described as areas of high endemism for southern South America.

Keywords: phylogeny, cladistics, iguanids, South American lizards