A Review of Lizards of the Liolaemus wiegmannii Group (Squamata, Iguania, Tropiduridae), and a History of Morphological Change in the Sand-Dwelling Species

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org..Herpetologists' League is collaborating with JSTOR to digitize, preserve and extend access to Herpetological Monographs.ABSTRACT: The wiegmannii group of Liolaemus includes L. lutzae, L. occipitalis, L. multimaculatus, L. rabinoi, L. riojanus, L. salinicola, L. scapularis, and L. wiegmannii; the status of L. cranwelli is uncertain, but is here considered a synonym of L. wiegmannii. The morphological characteristics of the wiegmannii group as a whole are described, and a taxonomic review, together with descriptions, distributions, and natural histories are presented for each species. This study then investigates the sequence of morphological changes that accompanied the evolution of the wiegmannii group. Seven of these, referred to here as the "sand-lizards" are confined to a substrate of loose, aeolean sand with extensive open dunes or sand flats. All of these species are members of a more inclusive clade, the boulengeri group. A phylogenetic analysis of the boulengeri group, based on 39 morphological and one behavioral character, produced a single most parsimonious tree that included the wiegmannii group as a fully resolved clade. This clade has a pectinate topology, with the following relationships: wiegmannii (lutzae (salinicola (scapularis (occipitalis (multimaculatus (riojanus + rabinoi)))))), with sand lizards represented by the last seven species, i.e., L. wiegmannii is the sister taxon to the sand lizards.Many of the morphological and behavioral transformations that occur at the origin of, and subsequently within the sand lizards, facilitate life on and under the surface of loose, wind-blown sand. Rapid diving and burial under the sand may be facilitated by a wedge-shaped snout with numerous small scales on the dorsal and lateral surfaces of the head, a sharp keel formed by the scales of the lower jaw, and a serrate margin on the shoulders and edges of the tail. Breathing under sand by vertical movement of the sternum may be facilitated by a wider sternum, with the fontanel reduced or absent, and a short median interclavicle process. A small ear opening, projecting ciliary scales, and a partly countersunk lower jaw should help to exclude sand from body openings. Fringes of projecting scales on the toes, and smooth, non-imbricate scales on the palms and soles should facilitate surface locomotion on sand. Reduction in dorsal sexual dicromatism, and close substrate color and pattern matching render them cryptic on the sand. Burial as a means of nocturnal retreat occurs in the sand lizards and most other species of the boulengeri group, but rapid diurnal burial as a means of escape occurs only in L. wiegmannii and the sand lizards. RESUMEN: El grupo wiegmannii de Liolaemus inc...

Sexual dimorphism in Liolaemus occipitalis (Iguania, Tropiduridae)

“…Differences in the color pattern of females and males were observed in several Liolaemus species, with males generally being more colorful (ETHERIDGE, 2000). In L. lutzae Mertens, 1938, ROCHA (1996 observed orange colors in the ventral side of the thighs.…”

“…Males of L. multimaculatus Boulenger, 1885, L. rabinoi Cei, 1974, andL. salinicola Laurent, 1986 present black blotches in the throat (ETHERIDGE, 2000). These color differences are quite probably associated to intra-and intersexual recognition.…”

Potential distribution of the endangered endemic lizard Liolaemus lutzae Mertens, 1938 (Liolaemidae): are there other suitable areas for a geographically restricted species?

“…However, only three species, all of them sand-dwellings (Etheridge, 2000), are presently known to occur in Brazil: L. arambarensis Verrastro, Veronese, Bujes and Dias-Filho, 2003 and L. occipitalis Boulenger, 1885, both from coastal sandy habitats from southern Brazil, and Liolaemus lutzae Mertens, 1938, endemic to the restinga habitats of Rio de Janeiro State, southeastern Brazil (Rocha et al, 2005). Liolaemus lutzae is a small sand-dwelling lizard (51-80 mm snout-vent length when adult; Rocha, 1992).…”

Historical Biogeography of a Clade of Liolaemus (Iguania: Liolaemidae) based on ancestral areas and dispersal-vicariance analysis (DIVA)

“…Although in the last years many works have been focused on the phylogeny of Liolaemus (Ortiz, 1981;Etheridge, 1995, Halloy et al 1998Young-Downey, 1998;Etheridge, 2000;Schulte et al 2000), they are not useful for a biogegraphic analysis because they are focused on subgroups or the genus is not fully represented. The cladistic analysis on the chiliensis group recently performed by Lobo (2001Lobo ( , 2005 differs from the other studies in having the chiliensis group, which is half the genus Liolaemus, fully represented.…”