PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY CENTRAL PARK WEST AT 79TH STREET, NEW YORK, NY 10024 Number 00, 27 pp., 7 figures, 3 tables , 2007 A New Genus of Microteiid Lizard from the Atlantic Forests of State of Bahia, Brazil, with a New Generic Name for Colobosaura mentalis, and a Discussion of Relationships Among the Heterodactylini (Squamata, Gymnophthalmidae) MIGUEL TREFAUT RODRIGUES1,2, KATIA CRISTINA MACHADO PELLEGRINO3, MARIANNA DIXO4, VANESSA KRUTH VERDADE2, DANTE PAVAN2, ANTOˆ NIO JORGE SUZART ARGOLO5, AND JACK W. SITES, JR.6 ABSTRACT A new genus and species of microteiid lizard is described from a series of specimens obtained in the leaf litter at Una (15u109S, 39u039W) in the Atlantic forest of southern Bahia, Brazil. It is characterized by the presence of prefrontals, frontoparietals, parietals, and interparietal; parietals longer than wide; distinct ear openings and eyelids; two pairs of genials, absence of collar and occipital scales; dorsal scales anteriorly smooth and becoming gradually lanceolate and mucronate posterior to the forelimb; and four regular transverse series of smooth ventrals that are longer than wide, identical in size. A phylogenetic analysis based on external morphology, osteology, and molecular data confirms this new lizard as a member of the Heterodactylini radiation of Gymnophthalminae. The topology recovered by maximum parsimony (MP) analyses reveals that its closest relatives are the sister taxa Colobosaura modesta and Iphisa elegans (BS 5,50%; 1Division of Vertebrate Zoology (Herpetology), American Museum of Natural History. 2Universidade de Sa˜o Paulo, Instituto de Biocieˆncias, Departamento de Zoologia, Caixa Postal 11.461, CEP 05422-970, Sa˜o Paulo, Brazil ([email protected]; [email protected]; [email protected]). 3Universidade Federal de Sa˜o Paulo, Campus Diadema, Sa˜o Paulo, Brazil ([email protected]). 4Universidade de Sa˜o Paulo, Instituto de Biocieˆncias, Departamento de Ecologia ([email protected]). 5Universidade Estadual Santa Cruz, Ilhe´us, Bahia, Brazil ([email protected]). 6Department of Integrative Biology and M. L. Bean Life Science Museum, Brigham Young University, Provo, Utah, US 84602 ([email protected]). Copyright E American Museum of Natural History 2007 ISSN 0003-0082 American Museum Novitates novi-496-00-01.3d 26/2/07 16:51:49 1 Cust # 496 2 AMERICAN MUSEUM NOVITATES NO. 00 Bremer value 5 2) and the partitioned Bremer indexes indicated that the largest contribution to this relationship comes from morphology; Colobosaura mentalis, for which a new generic name is here proposed, is basal to this radiation. Our analyses confirm a previous hypothesis suggesting Stenolepis as a member of the Heterodactylini radiation and that the clade composed of Colobodactylus and Heterodactylus is the sister group of the clade formed by Colobosaura mentalis- Stenolepis (BS 5 100; Bremer value 5 18), Colobosaura modesta-Iphisa (BS 5,50%; Bremer value 5 1), and the new genus here described. The support for Heterodactylini monophyly, on the basis of combined MP analyses is higher (BS 5 96, Bremer value 5 11) than that previously found in molecular-based studies only. Partitioned Bayesian methodology combining molecular and morphological data sets recovered the new genus as the sister taxon (PP 5 0.94) of the clade (PP 5 0.94) formed by I. elegans-C. modesta (PP 5 0.51) and C. mentalis-S. ridley (PP 5 1.0). An alternative topology demonstrating a paraphyletic Heterodactylini is only weakly supported (PP 5 0.63). Based on the MP topology we discuss tentative scenarios for the evolution of Heterodactylini. INTRODUCTION have been made to infer relationships among the genera (Myers and Donnelly, 2001; Hoyos, The Gymnophthalmidae represent a large 1998), and one entirely new clade of micro- South and Middle American radiation (41 teiids (characterized by scincoid scales) was genera and about 180 species) of small to recognized (Rodrigues, 1991a, b, c). All of medium-sized lizards occurring in terrestrial, these initiatives were based on morphology. arboreal, fossorial, and semiaquatic habitats Only in this century, the first extensive extending from sea level to the high Andes molecular-based phylogenetic hypothesis was (Pellegrino et al., 2001; Doan, 2003; Doan proposed for Gymnophthalmidae, which were and Castoe, 2005; Rodrigues et al., 2005). recovered as monophyletic (Pellegrino et al., Taxonomic study of these so-called ‘‘micro- 2001). Based on the study of 26 representatives teiid’’ lizards (Ruibal, 1952) has been compli- of the 36 genera recognized at the time, four cated by the rarity of specimens in collections, subfamilies were recognized: Alopoglossinae, which limits studies of geographical and Rhachisaurinae, Cercosaurinae (with two individual variation, and convergence in char- tribes, Cercosaurini and Ecpleopini), and acter complexes (e.g., body elongation, limb Gymnophthalminae (also with two tribes: reduction, earlessness, lack of eyelids, and the Gymnophthalmini and Heterodactylini). fusion/fission of some major head scales), Genera not represented in the molecular which has rendered higher-level taxonomy analysis of Pellegrino et al. (2001) were of the Gymnophthalmidae problematic. Bou- tentatively allocated to the recognized clades lenger (1885) first organized their chaotic on the basis of morphology. Pellegrino et al. taxonomy by recognizing three groups of also demonstrated the paraphyly of several microteiids and another group (macroteiids) microteiid genera, giving support to previous in the Teiidae. After this, several attempts hypotheses suggesting extensive character were made to validate or understand interge- convergence, and making understandable the neric relationships between and within the unsuccessful attempts of previous classifica- boulengerian groups (Ruibal, 1952; MacLean, tions. 1974; Presch, 1980; Harris, 1985; Sullivan and Castoe et al. (2004) using only four of the Estes, 1997; Hoyos, 1998). The relationships five genes explored by Pellegrino et al. (2001) between gymnophthalmids and teiids (macro- and a slightly improved sampling design teiids) were generally recognized, with micro- (twelve additional species and one additional teiids considered either as a distinct family genus), reanalyzed the Pellegrino et al. (2001) (Presch, 1983, 1988; Estes, 1983; Estes et al., data. Their results, based on partitioned 1988) or as a subfamily (MacLean, 1974; Bayesian analyses, were highly consistent Presch, 1978, 1980) of Teiidae. In the last two with those obtained by Pellegrino et al. decades, several new taxa of the Gymno- (2001) with the following higher-level taxo- phthalmidae have been described (Rodrigues, nomic changes: (1) Ptychoglossus was includ- 1991a, 1991b, 1991c, 1997; Myers and ed in Alopoglossinae; (2) Heterodactylini Donnelly, 2001; Kok, 2005); some attempts and Gymnophthalmini were combined in American Museum Novitates novi-496-00-01.3d 26/2/07 16:51:49 2 Cust # 496 2007 RODRIGUES ET AL.: MICROTEIID LIZARD 3 a Gymnophthalminae without tribal divisions; biodiversity, phylogenetic relationships within (3) Ecpleopini was raised to subfamily status, the family Gymnophthalmidae remain poorly and (4) Bachia was allocated to the new tribe known. We therefore follow Rodrigues et al. Bachiini within the Cercosaurinae. (2005) and use the classification proposed Since then, both schemes have been referred by Pellegrino et al. (2001) for the Gymno- in the literature (Doan and Castoe, 2005; phthalminae until extensive character and Rodrigues et al., 2005). In a paper focused on taxon sampling has been completed. clarification of the phylogenetic taxonomy of Pellegrino et al. (2001) defined the tribe the cercosaurines, Doan and Castoe (2005) Heterodactylini, on the basis of molecular followed the arrangement of Castoe et al. evidence, to include the genera Colobo- (2004). They described two new genera dactylus, Colobosaura, Heterodactylus, Iphisa, (Potamites and Petracola) to accommodate and probably the genus Stenolepis (which was a group of species formerly included in not sampled by Pellegrino et al.; or Castoe et Neusticurus and Proctoporus, respectively, al. 2004) on the basis of morphology. In this and resurrected Riama to allocate another paper we include the latter genus and add group of Proctoporus. Rodrigues et al. (2005) morphological data (completely absent from fully agreed with the reallocation of the studies of both Pellegrino et al., and Ptychoglossus, but continued to follow the Castoe et al.) to extend our studies of relation- proposal by Pellegrino et al. (2001) in other ships within the Heterodactylini. We describe respects because they considered the other an unknown genus and species within this changes proposed by Castoe et al. (2004) clade, and discuss its relationships to the other premature; this decision was based on the heterodactyline genera. The first specimen of evidence provided by morphological charac- the new taxon came to our attention in the ters included in the study of Rodrigues et al. mid-1990s, when the first author received for Although the study by Rodrigues et al. (2005) examination a lizard obtained at Ilhe´us, state was based on a smaller data set, they included of Bahia, Brazil. It was sent by P.E. Vanzolini representatives of the major clades to test the with a note saying that it was possibly a new relationships of the new genus described species of Colobosaura. That specimen was (Dryadosaura) in that paper, and their com- discovered during the process of reorganiza- bined morphological and molecular