We examined skeletons of seven adult and juvenile specimens of Liolaemus azarai that were cleared and double-stained. The states of twenty three postcranial skeleton characters were described and compared with others Liolaemus species. Our findings complement the current knowledge about the osteological variation in Liolaemus and the character states may include in a data matrix to future phylogenetic studies.Fil: Gonzalez Marin, Maria Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Hernando, Alejandra Beatriz. Universidad Nacional del Nordeste. Facultad de Ciencias  Exactas Naturales y Agrimensura; Argentin

Gonzalez Marin, Maria Andrea

Hernando, Alejandra Beatriz

Phyllomedusa Journal of Herpetology

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135Phyllomedusa - 12(2), December 2013Phyllomedusa 12(2):135–141, 2013© 2013 Departamento de Ciências Biológicas - ESALQ - USP ISSN 1519-1397 (print)ISSN 2316-9079 (online)Received 25 September 2013.Accepted 25 October 2013.Distributed December 2013.ShOrt COmmuniCatiOnNotes on the postcranial osteology of the sand lizard Liolaemus azarai (Squamata: Liolaemidae)Andrea González-Marín1 and Alejandra Hernando21 Grupo de Herpetología Patagónica, CENPAT-CONICET, Boul. Almt. G. Brown 2915, Puerto Madryn, Chubut, Argentina. E-mail: andrea_gmarin@hotmail.com.2 Laboratorio de Herpetología, Facultad de Ciencias Exactas y Naturales y Agrimensura, Universidad Nacional del Nordeste. Av. Libertad 5400, Corrientes (3400), Argentina.Keywords: Argentina, osteological features, Paraguay, skeleton, variation.Palavras-chave: Argentina, características osteológicas, esqueleto, Paraguai, variação.The liolaemid lizard genus Liolaemus Wiegmann, 1834 comprises more than 235 species described and is widely distributed in southern South America (Avila et al. 2010, Lobo et al. 2010, Breitman et al. 2013). It is one of three genera of Liolaemidae. Liolaemus differs osteologically from Ctenoblepharys Tschudi, 1845 and Phymaturus Gravenhorst, 1837 in several characters. The lateral borders of orbitonasal fenestra are formed by down growths of the frontals. The supratemporal is enclosed in a groove on the ventral surface of the paraoccipital process of parietal. The dentary extends beyond the posterior lingual process of coronoid. The anterior process of the angular is reduced or absent, and the posterior coracoid fenestra is present (Etheridge 1995). Osteological studies of the diverse genus Liolaemus are scarce. The cranial osteology of L. lutzae, L. signifer, and L. occipitalis was described by Fabián-Beurmann and Vieira (1980) and Simões-Lópes and Krause (1988). Keller and Krause (1986) provided a description of the appendicular skeleton of L. occipitalis, and da Silva and Verrastro (2007) reported on the postcranial axial skeleton of L. arambarensis. In his phylogenetic analysis of the L. wiegmannii Group, Etheridge (2000) reported a sequence of morphological transformations that facilitate subterranean breathing; these include changes in the sternum and interclavicle. Recently, Lobo and Abdala (2001) identified 35 osteological characters of Liolaemus that they considered to be variable and phylogenetically informative. We examined 23 postcranial skeletal characters of Liolaemus azarai Avila, 2003 and the distribution of each of these in Liolaemus to provide more information about mophological variation in the genus.136Phyllomedusa - 12(2), December 2013González­Marín and HernandoLiolaemus azarai is a small lizard (54.3 and 48.7 mm snout-vent length in males and females, respectively) that inhabits sandy dunes in northeastern Argentina and on Yacyretá Island (Paraguay) (Álvarez et al. 2003, Avila 2003). This lizard is a member of the L. wiegmannii Group, which also includes L. arambarensis Verrastro, Veronese, Bujes and Dias Filho, 2003; L. cuyumhue Avila, Morando, Pérez and Sites, 2009; L. lutzae Mertens, 1938; L. multimaculatus (Duméril and Bibrón, 1837); L. occipitalis Boulenger, 1885; L. rabinoi (Cei, 1974); L. riojanus Cei, 1979; L. salinicola Laurent, 1986; L. scapularis Laurent, 1982; and L. wiegmannii (Duméril and Bibrón, 1837).We examined skeletons of seven adult and juvenile specimens of Liolaemus azarai that were cleared and double-stained following the methodology of Dingerkus and Uhler (1977). The specimens examined are deposited in the herpetological collection of the Universidad Nacional del Nordeste (UNNEC; Appendix I). Of the 23 postcranial skeleton characters that we examined, 17 were proposed by Lobo and Abdala (2001) and six others were extracted from the literature, as follow: number of sternal and xiphisternal ribs (Etheridge 1965, Torres-Carvajal 2004); shape of sternum and extent of medial process of interclavicle (Etheridge 2000); and condition of cartilaginous ends of Cervical Ribs V and VI (da Silva and Verrastro 2007). Measurements were made with digital calipers (precision 0.01 mm) and seven ratios were calculated from the morphometric data. Illustrations were prepared with the aid of a stereomicroscope equipped with a camera lucida.The postcranial skeletal characters examined and their corresponding states in Liolaemus azarai are listed in Tables 1 and 2 and depicted in Figures 1–3.Six osteological features characterizing Liolaemus azarai were described in most of 24 species analyzed by Lobo and Abdala (2001). These include presence/absence of the following features: Cervical Rib III; clavicle fenestra; posterior process of sternum; single, median sternal fontanelle; anteriorly oriented pubis; and expansion of free end of hypoischium. In L. azarai, 10 morphological characters do not vary, and six others vary as follow (Table 1): (1) cartilaginous distal ends of Cervical Ribs V (entire/divided, 5/2 specimens); (2) cartilaginous distal ends of Cervical Rib VI (entire/divided, 3/4); (3) number of sternal ribs (2/3, 4/3 specimens); (4) number of xiphisternal ribs (2/3, 3/4 specimens); (5) number of postxiphisternal (3/4, 2/5 specimens); and (6) length of the median process of the interclavicle (long/short, 3/4).The ranges and means of the seven mor-phometric features (lateral process of interclavicle length/skull length; maximum diameter of coracoid fenestra/maximum diameter of scapular fenestra; hypoischium length/skull length; uneven xiphisternal rod length/skull length; clavicle length/ skull length; clavicle width/ skull length; sternum width/ sternum length) recorded for Liolaemus azarai fall within the variation expected for the genus (fide Lobo and Abdala 2001). Our findings complement the current knowledge about the osteological variation in Liolaemus and these character states may include in a data matrix to future phylogenetic studies.Acknowledgments—We thank Blanca Alva-rez and Ligia Krause who provided helpful suggestions for improvement of the manuscript, and Roberto Aguirre and Guido Fernández Brundo for help in the preparation of drawings. This study was supported by grants from Secre taría General de Ciencia y Técnica, Universidad Nacional del Nordeste (F 019- 2008). Dirección de Recursos Naturales from Corrientes (Argentina) provided collecting permits.137Phyllomedusa - 12(2), December 2013Notes on the postcranial osteology of the sand lizard Liolaemus azaraiCharacters Character states SpeciesCervical Rib IIIAbsentL. azarai, L. arambarensis, L. bibronii, L. bitaeniatus, L. boulengeri, L. cf. silvanae, L. grosseorum, L. koslowskyi, L. lemniscatus, L. magellanicus,  L. neuquensis, L. pictus,  L. pseudoanomalus, L. tenuisPresent L. kingiiVariable (present/absent) L. buergeri, L. chacoensis, L. chiliensis,  L. nigroviridisCervical Rib IV, cartilaginous endEntire L. arambarensis, L. lemniscatus, L. tenuisDivided L. bitaeniatus, L. cf. silvanae,  L. neuquensis, L. pictusVariable (entire/divided)L. azarai, L. boulengeri, L. bibronii,  L. buergeri, L. chacoensis, L. chiliensis, L. grosseorum, L. kingii, L. koslowskyi, L. magellanicus, L. nigroviridis,  L. pseudoanomalusCervical Rib V, cartilaginous endDivided L. arambarensisVariable (entire/divided) L. azaraiCervical Rib VI, cartilaginous endDivided L. arambarensisVariable (entire/divided) L. azaraiSternal ribs, number3 L. arambarensis, L. occipitalis2 or 3 L. azaraiXiphisternal ribs, number2 L. arambarensis, L. occipitalis2 or 3 L. azaraiElongated postxiphisternal ribs, range5–7 L. kingii and L. lineomaculatus Groups3–5 L. chiliensis Group2–5 L. signifer Group3 or 4 L. wiegmannii Group: L. azarai,  L. salincolaSternal fontanelleVariable (divided or absent)L. riojanus, L. multimaculatus,  L. occipitalis, L. salinicola, L. scapularis, L. arambarensisSingle, medianL. wiegmannii Group: L. azarai,  L. wiegmannii, L. lutzae.L. kingii, L. archeforus, L. lineomaculatus, L. chiliensis, L. signifer and  L. boulengeri Groups.Sternum shapeWider than long L. azarai, L. multimaculatus, L. occipitalis, L. riojanus, L. salinicola, L. scapularisAs wide as long L. lutzae and L. wiegmanniiTable 1.  Character states of postcranial skeleton of Liolaemus species including L. azarai. Sources: Keller and Krause 1986, Etheridge 1995, 2000, Lobo and Abdala 2001, da Silva and Verrastro 2007, this study.138Phyllomedusa - 12(2), December 2013Posterior process of sternumVariable (absent/present) L. pictus, L. tenuisAbsentL. wiegmannii Group: L. azarai,  L. arambarensis.L. kingii, L. archeforus, L. lineomaculatus, L. chiliensis, L. signifer and L. boulengeri Groups.ClavicleVariable (fenestrated/ not fenestrated) L. tenuis, L. koslowskyiNot fenestratedL. wiegmannii Group: L. azarai,  L. arambarensis, L. occipitalis.L. lineomaculatus, L. chiliensis, L. signifer and L. boulengeri Groups.Median process of interclavicleVariable (Not reaching/reaching level of anteromost pair of sternal ribs)L. azarai, L. lutzae, L. wiegmannii,  L. salinicolaNot reaching level of anteromost pair of sternal ribsL. occipitalis L. riojanus,  L. multimaculatus, L. scapularis,  L. arambarensisFree end of hypoischiumExpanded L. tenuis, L. kingiiNot expandedL. azarai, L. buergeri, L. chacoensis,  L. chiliensis, L. cf. silvanae, L. koslowskyi, L. lemniscatus, L. magellanicus,  L. neuquensis, L. pictusVariable (expanded/ not expanded) L. bibronii, L. boulengeri, L. grosseorum, L. nigroviridis, L. pseudoanomalusPubis orientationPerpendicular to vertebral column L. pseudoanomalusForwardL. wiegmannii Group: L. azarai,  L. occipitalisL. kingii, L. archeforus, L. lineomaculatus, L. chiliensis, L. signifer and  L. boulengeri Groups.Bladelike process of the tibiaPresent L. montanus Group: including L. azaraiAbsent L. kingii, L. archeforus, L. lineomaculatus, L. chiliensis Groups, L. pseudoanomalusCaudal vertebrae without chevrons, number1 L. capillitas2 L. cf. quilmes, L. dorbignyi,  L. grosseorum, L. salinicola, L. tenuis3L. bibronii, L. cf. silvanae, L. chacoensis,  L. chiliensis, L. koslowskyi,  L. lemniscatus, L. orientalis, L. ramirezae4 L. azarai, L. ornatusVariable (2/3)L. boulengeri, L. burgueri, L. kingii, L. magellanicus, L. neuquensis,  L. nigroviridis, L. pictusGonzález­Marín and HernandoTable 1.  Continued.139Phyllomedusa - 12(2), December 2013Notes on the postcranial osteology of the sand lizard Liolaemus azaraiFigure 2. Clavicle, interclavicle, sternum, and sternal, xiphisternal, and postxiphisternal ribs of Liolaemus azarai in ventral view (UNNEC 4333, left; UNNEC 9659, right). Abbreviations: Cl, clavicle; I, interclavicle; Pr, postxiphisternal ribs; S, sternum; Sf, sternal fontanelle; Sr, sternal ribs; xf: xiphisternal ribs; xr, xiphisternal rods.Figure 1. Cartilaginous ends of cervical ribs IV–VI of Liolaemus azarai (UNNEC 10588, left; UNNEC 4333, right).Figure 3. (A) Dorsal view of left tibia of Liolaemus azarai (UNNEC 10587, left). (B) Ventral view of pelvic girdle of L. azarai (UNNEC 9656, right). Abbreviations: Ep:, epipubis; Hp, hypoischium; Il, ilium; Is, ischium; Pb, pubis; Tb, tibia; Tbp, bladelike process of the tibia.140Phyllomedusa - 12(2), December 2013González­Marín and HernandoReferencesÁlvarez, B. B., R. H. Aguirre, J. A. Céspedez, A. B. Hernando, and M. E. Tedesco. 2003. Herpetofauna del Iberá. Fauna del Iberá. Corrientes, Argentina. EUDENE Press.Avila, L. J. 2003. A new species of Liolaemus (Squamata: Liolaemidae) from northeastem Argentina and southem Paraguay. Herpetologica 59: 283–292.Avila, L. J., M. Morando, D. R. Pérez, and J. W. Sites. 2010. A new species of the Liolaemus elongatus clade (Reptilia: Iguania: Liolaemini) from Cordillera del Viento, northwestern Patagonia, Neuquén, Argentina. Zootaxa 2667: 28–42.Breitman, M.F., M. Morando, and L. J. Avila. 2013. Past and present taxonomy of the Liolaemus lineomaculatus section (Liolaemidae): is the morphological arrangement hypothesis valid? Zoological Journal of the Linnean Society 168: 612–668.da Silva, C. M. and L. Verrastro. 2007. Descrição do esqueleto axial de Liolaemus arambarensis Verrastro, Veronese, Bujes and Diaz Filho (Iguania. Liolaemidae): regiões pré-sacral e sacral. Revista Brasileira de Zoologia 24: 1–11. Dingerkus, G. and L. D. Uhler. 1977. Enzyme clearing of alcian blue stained whole small vertebrates for demons-tration of cartilage. Stain Technology 52: 229–239.Etheridge, R. 1965. The abdominal skeleton of lizards in the family Iguanidae. Herpetologica 21: 161–168.Etheridge, R. 1995. Redescription of Ctenoblepharys adspersa Tschudi, 1845, and the taxonomy of Liolaemi-Table 2. Ratios based on measurements of ten postcranial characters skeleton of Liolaemus azarai. Morphometric ratios Range Mean ± SDLateral process of interclavicle length/skull length 0.24–0.28 0.26 ± 0.017Maximum diameter of coracoid fenestra/maximum diameter of scapular fenestra0.3–0.7 0.47 ± 0.13Hypoischium length/skull length 0.34–0.5 0.43 ± 0.069Uneven Xiphisternal rod length/skull length 0.02–0.1 0.06 ± 0.026Clavicle length/skull length 0.25–0.4 0.32 ± 0.06Clavicle width/skull length 0.01–0.09 0.07 ± 0.017Sternum width/sternum length 0.75–1.12 0.9 ± 0.14nae (Reptilia: Squamata: Tropiduridae). American Museum Novitates 3142: 1–34 .Etheridge, R. 2000. A review of lizards of the Liolaemus wiegmannii group (Squamata, Iguania, Tropiduridae), and a history of morphological change in the sand-dwelling species. Herpetological Monographs 14: 293–352.Fabián-Beurmann, M. E. and M. I. Vieira. 1980. Sobre a osteologia craniana de Liolaemus occipitalis Boulenger, 1885, L. lutzae Mertens, 1938 e L. multiformis simonsii Boulenger, 1902 (Lacertilia, Iguanidae). Iheringia, Série Zoologia 56: 95–102. Keller, C. and L. Krause. 1986. The appendicular skeleton of Liolaemus occipitalis Boulenger, 1885 (Sauria, Igua-nidae). Revista Brasileira de Biologia 46: 727–740.Lobo, F. and C. Abdala. 2001. Variación morfológica en el esqueleto de Liolaemus (Iguania: Liolaemidae). Búsqueda y descripción de caracteres. Cuadernos de Herpetología 15: 119–135.Lobo, F., R. E. Espinoza, and S. Quinteros. 2010. A critical review and systematic discussion of recent classification proposals for liolaemid lizards. Zootaxa 2549: 1–30.Simões-Lópes, P. C. A. and L. Krause. 1988. Osteologia do sincrânio de Liolaemus occipitalis Boulenger, 1885 (Sauria: Iguanidae). Revista Brasileira de Zoologia 5: 491–508.Torres-Carvajal, O. 2004. The abdominal skeleton of tropi-durid lizards (Squamata: Tropiduridae). Herpetologica 60: 75–83.Editor: Linda Trueb141Phyllomedusa - 12(2), December 2013Notes on the postcranial osteology of the sand lizard Liolaemus azaraiAppendix I. Specimens Examined.ARGENTINA: Corrientes: Isla Apipé Grande: Puerto Arazá (27o28'42'' S, 56o56'34'' W) 2 %, 21.IX.2007, V. Zaracho col. (UNNEC 09656, UNNEC 09659); &, 4.XII.2007, V. Zaracho col. (UNNEC 09770); 2 %, 20.IX.2009, V. Zaracho col. (UNNEC 10587, UNNEC 10588); San Miguel: Curuzú Laurel (27o56'11'' S, 57o30'04'' W) %, 14.III.1992, R. Aguirre col. (UNNEC 04333); Concepción: Estancia Rodeo Porá (28o33'11'' S, 58o06'44'' W) %, 13.XII.2001, R. Aguirre col. (UNNEC 07634).

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Notes on the postcranial osteology of the sand lizard Liolaemus azarai (Squamata: Liolaemidae)

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Notes on the postcranial osteology of the sand lizard Liolaemus azarai (Squamata: Liolaemidae)

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