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Zootaxa 3616 (2): 173–189 ISSN 1175-5326 (print edition) www.mapress.com/zootaxa/ Article ZOOTAXA Copyright © 2013 Magnolia Press ISSN 1175-5334 (online edition) http://dx.doi.org/10.11646/zootaxa.3616.2.6 http://zoobank.org/urn:lsid:zoobank.org:pub:D6F85F14-2D4E-4B53-9B40-3B6E9BE723FF A new species of Bachia Gray, 1845 (Squamata: Gymnophthalmidae) from the Eastern Brazilian Cerrado, and data on its ecology, physiology and behavior MAURO TEIXEIRA JR1,3, RENATO SOUSA RECODER1, AGUSTÍN CAMACHO1, MARCO AURÉLIO DE SENA1, CARLOS ARTURO NAVAS2 & MIGUEL TREFAUT RODRIGUES1 1Laboratório de Herpetologia, Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, CEP 05508-090, São Paulo, SP, Brazil 2Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, CEP 05508-090, São Paulo, SP, Brazil 3Corresponding author. E-mail: [email protected] Abstract A new species of Bachia of the bresslaui group, Bachia geralista sp. nov., is described from Planalto dos Gerais, an old and partially dissected plateau extending along the Cerrados of Bahia, Minas Gerais and Tocantins states, Brazil. The new species is morphologically similar to B. bresslaui, with which it has been confused; however head scalation resembles other species from sandy spots within the Cerrado (B. psamophila and B. oxyrhina). Like in B. psamophila and B. oxyrhi- na, the shovel-shaped snout of the new species is highly prominent, a typical trait of psammophilous habits in other gym- nophthalmids. The examination of specimens of B. bresslaui from several populations within the Cerrado revealed great variation among localities, leading to the reidentification of a specimen from Utiariti, Mato Grosso, previously referred to in the literature as the second record of B. bresslaui, as the recently described B. didactyla, suggesting that cryptic diversity might remain still undiscovered within this genus in the Cerrado. Despite occurring in a relatively open Cerrado, thermal physiology of Bachia geralista sp. nov. restricts its occurrence to shaded microhabitats within this habitat. Key words: Bachia geralista sp. nov., psammophilous habits, Peruaçu, limb reduction, fossoriality. Introduction At the end of the XVIII century Bonnaterre (1789) described Chalcides flavescens, a small worm-like lizard from South America, with vestigial limbs. Few decades later Duméril and Bibron (1839) described C. dorbignyi, a second South American species from Bolivia. Later, Gray (1845) recognized Duméril and Bibron’ species as belonging to a distinct genus, and described Bachia to accommodate it. More than 150 years has passed and the genus Bachia, including Bonnaterre’ species, currently comprises 22 species distributed mostly over the tropical South America, and southern Central America (Dixon 1973; Castrillon & Strussmann 1998; Kizirian & McDiarmid 1998; Rodrigues et al. 2007; Rodrigues et al. 2008; Freitas et al. 2011). Forest dwelling species of Bachia frequently show a rounded snout, and fingers and toes relatively developed (Dixon 1973). However, in the last few decades, several species have been described from the open areas within the Cerrado of Central Brazil (Castrillon & Strussmann 1998; Rodrigues et al. 2007; Rodrigues et al. 2008; Freitas et al. 2011), all showing reduced limbs, and those from sandy habitats (e.g. B. micromela Rodrigues, Pavan & Curcio 2007, B. psamophila Rodrigues, Pavan & Curcio 2007 and B. oxyrhina Rodrigues, Camacho, Nunes, Recoder, Teixeira, Valdujo, Ghellere, Mott & Nogueira 2008) also showing reduction on head scalation and a shovel-like snout (Rodrigues et al. 2007, Rodrigues et al. 2008). The relationship between morphology, ecology, physiology and behavior of species are basic to recognize potential limitations to their ecological or geographical distribution, and support further conservation actions or evolutionary studies. However, as for most gymnophthalmids, these traits are very poorly known in Bachia (Colli 1998; Wiens et al. 2006; Henderson & Powell 2009; Bentz et al. 2011). Accepted by S. Carranza: 4 Jan. 2013; published: 19 Feb. 2013 173 Based on a series of specimens obtained at the southernmost end of Planalto dos Gerais, in the eastern part of Brazilian Cerrado, as well as on exemplars from nearby localities, we recognize those populations, which have been previously included in the widely distributed B. bresslaui (Amaral, 1935) (Rodrigues et al. 2008), as a distinct new species which we describe, providing data on its ecology, physiology and behavior, and discussing the implications of the morphological variation found within B. bresslaui. Material and methods Field sampling. Specimen collection was made through pitfall traps with drift fences and active search. The pitfall traps were installed throughout the main habitats at Parque Nacional das Cavernas do Peruaçu: 15 traps on dry forest habitats; 15 on savanna; 17 on an arborescent scrubland, locally known as “carrascos”, and two on riparian evergreen forest. Each trap was composed of four 30 L buckets connected by 4 m long vertical plastic fences, which remained opened for 20 consecutive days each sampling period: January 2008 and 2009 (rainy seasons), and July 2008 and 2009 (dry seasons); totalizing an effort of 14.560 buckets/day. Active searches were performed during July 2008 and January 2009, and only at the savanna habitat. Searches consisted in racking all the leaf litter, trunks or shallow soil of haphazardly selected microhabitat patches, divided in three categories: (i) open areas, (ii) bushes and (iii) trees. At each patch, the individuals found were collected, and the size of the patch estimated by measuring its two major perpendicular axis and using the ellipse’s formulae to calculate the area. Concomitantly to that, environmental temperatures were measured hourly by HOBO data loggers (resolution 1ºC, with white probe weighting 1g), laid at two different microhabitats, (i) ground’s surface or the leaf litter and (ii) the deepest limit of the loose soil (usually 2cm), in both open areas and under vegetation, totalizing four microhabitats. In the latter case, the logger probe was covered by leaf litter plus loose soil layer. To show potential thermal restrictions imposed by the different microhabitats over Bachia’s ecological distribution at this site, maximum and minimum temperatures were compared among microhabitats. When not designated to physiological experimentation, or after that, the individuals were sacrificed, fixed in 10% formalin, preserved in 70% ethanol, and housed at Museu de Zoologia da Universidade de São Paulo, São Paulo, Brazil. Behavioral and physiological observations. Escape and defensive behavior of some individuals was observed and annotated during data collection and within set ups for focal animal trials (10 individuals). These set ups consisted of a recipient filled with sandy soil 4 cm’s deep, having half of its area covered by leaf litter. In each trial, a single specimen was placed in one of both substrates (sand or sand covered by leaf litter), and its first reaction was categorized as: (i) slide, (ii) hide (meaning partial burrowing or hiding under leaf litter), or (iii) burrow. All ten specimens were subjected to trials in both substrates, in random order. Ten individuals, maintained for a year, where observed from 5:00 to 23:00. Animals were kept in plastic terraria, keeping together the groups found in single patches during fieldwork. All terraria received UV (L12:D12) and heating light (L10:D14), with diurnal thermal gradients ranging between 20º–45ºC, falling to 22–20ºC at nights. All lizards were fed with termites, and immature cockroaches and crickets. Water was provided every two days spraying it directly on leaf litter and terrarium walls. Thermal preferences were measured over the day and beginning of the night (8–19:30h, lights were switched off at 18:30) in thermal gradients ranging between 14–55ºC. A T-type thermocouple was fixed to the back of lizards using surgical tape, allowing body temperatures to be registered in a computer using a multiple thermocouple register (model 8018, Superlogics®). The critical thermal maximum was assessed through incidental (Cowles & Bogert 1944) miss function of the thermal chamber, set to 39ºC, that suddenly raised to 41ºC and cause the death of individuals. Morphology. Length measurements were taken after fixation to the nearest millimeter with a digital caliper; scale counts and observations of other morphological characters were performed with a stereomicroscope Zeiss STEMI SV6. Scale nomenclature follows Dixon (1973). Comparisons were made primarily through examined specimens housed in the herpetological collection of the Museu de Zoologia, Universidade de São Paulo (MZUSP) (Appendix I), and were supplemented with data from the literature (Vanzolini 1961; 1966; Dixon 1973; MacLean 1973; Avila-Pires 1995; Castrillon & Strussmann 1998; Colli et al. 1998; Rodrigues et al. 2007; Rodrigues et al. 2008; Freitas et al. 2011). 174 · Zootaxa 3616 (2) © 2013 Magnolia Press TEIXEIRA JR ET AL. Meristic characters were: (SO) supraoculars; (SC) superciliaries; (SL) supralabials; (TS) temporal, scales along each three oblique series of temporals; (FP) femoral pores; (PP) preanal pores; (PS) preanal shields; (SAB) scales around midbody; (DO) dorsals, between parietals to the row over the insertion of hindlimbs; (VE) ventrals, between interbrachial shields and preanal shields; (GU) gulars, between interbrachial and mental plates; (CA) caudals. The measurements were:

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