Squamate Reptiles of the central Chapada Diamantina, with a focus on the municipality of Mucugê, state of Bahia, Brazil

: We present the first species list of squamate reptiles for the central region of the Chapada Diamantina, with a focus on the municipality of Mucugê, state of Bahia Brazil. The data provided were mostly collected in the Caraíbas estate, during vegetation clearing operations for agriculture. The remnant records were collected from roadkills encountered in Mucugê and neighboring municipalities. We found 64 species of squamate reptiles including 35 species of snakes, 25 of lizards and four of amphisbaenians. These records have already yielded three species descriptions with others likely to follow. This is evidence of the poorly documented herpetological diversity of the Chapada Diamantina. The present work highlights the need for further research and the potential of less traditional data sources such as roadkills to improve the knowledge of the herpetofauna of extensive and megadiverse countries like Brazil.


Introduction
The Chapada Diamantina, the local name of the northern segment of the Serra do Espinhaço mountain ridge, is a mountainous region located within the Caating biome, crossing the state of Bahia from north to south (Ab`Saber 1977). Although dominated by semi-arid environments, the Chapada Diamantina has a wide range of ecosystems, a result of the topographic diversity, the distribution of water sources and drainages, and the present and past contacts with the Cerrado, Caatinga and the Atlantic Forest biomes (Queiroz et al. 2008).
The Chapada Diamantina has been targeted by a few studies of its flora (e.g. Queiroz et al. 2008;Giulietti and Wanderley 1995), insects (e.g. Lopes and Louzada 2008), mammals (e.g. Oliveira and Pessôa 2005), fish (e.g. Santos and Caramaschi 2008) and birds, which have had the most consistent surveying (e.g. Carvalhaes and Machado 2008). Nonetheless, its biodiversity remains greatly unknown, which explains its selection as a priority area for research on biodiversity in Brazil (Rodrigues 2003).
The herpetofauna of the Chapada Diamantina has only recently received attention from the scientific community, with a few surveys attempting to document the reptile and amphibian species present in the region. These studies have resulted in the description of several new species (Freitas 1999;Argôlo andFreitas 2000, 2002;Juncá 2005;Rodrigues et al. 2006Rodrigues et al. , 2009aFreitas et al. 2007aFreitas et al. , b, 2010Lugli and Juncá 2008;Mott et al. 2008).

Study site
The majority of the records were gathered at the Caraíbas estate (13°09' S, 41°24' W), district of Cascavel, municipality of Mucugê, state of Bahia, northeastern Brazil Abstract: We present the first species list of squamate reptiles for the central region of the Chapada Diamantina, with a focus on the municipality of Mucugê, state of Bahia Brazil. The data provided were mostly collected in the Caraíbas estate, during vegetation clearing operations for agriculture. The remnant records were collected from roadkills encountered in Mucugê and neighboring municipalities. We found 64 species of squamate reptiles including 35 species of snakes, 25 of lizards and four of amphisbaenians. These records have already yielded three species descriptions with others likely to follow. This is evidence of the poorly documented herpetological diversity of the Chapada Diamantina. The present work highlights the need for further research and the potential of less traditional data sources such as roadkills to improve the knowledge of the herpetofauna of extensive and megadiverse countries like Brazil.

Data collection
Data collection for the present study began opportunistically in 2000, mostly through records of snakes found as roadkills when the authors traveled through the region as part of consultancy work. This work was intensified from November 2004 to October 2008 through the fauna inventories conducted as part of the legally imposed mitigation measures for vegetation clearing, associated with land use changes in the Caraíbas estate, namely agriculture. At these field sites, the team followed the machinery clearing the vegetation to inventory the fauna being displaced during the process or killed by it. The surveys were conducted yearly by a team of 10 people, for approximately eight daily hours and for periods of 10 days at each stage of vegetation clearing. This totalizes a minimum of 32,000 man hours of survey effort. The surveys accompanied the clearing of 240 ha per year of native vegetation from 2005 to 2008, leading to a total of 960 ha. During these surveys 820 vertebrates were found, 74% of which were reptiles. From these individuals a proportion of those thought to represent undescribed species or otherwise relevant records were collected (NUFAU/IBAMA 021/2005), initially preserved in 10% formalin and afterwards moved to 70% alcohol. The specimens found as roadkills (IN-154/2007/IBAMA art-26) were initially preserved in 20% formalin and then moved to 70% alcohol. All the specimens were deposited in six referenced collections: For the species that were recorded during the surveys but for which it was not possible to collect any specimens, we used the relevant literature to provide support for their presence in the study area.

Results and Discussion
We recorded 64 species of squamate reptiles, belonging to 45 genera and 17 families. Snakes accounted for 35 species, 27 genera and six families, lizards for 25 species, 18 genera and 10 families, while amphisbaenians accounted for four species in a single genus (Table 1).
The work from which this species list originated has greatly contributed to increase the knowledge of the herpetofauna in the Chapada Diamantina region. Three species have already been described based on specimens collected during this research: the amphisbenian Amphisbaena uroxena (Figure 2A) and the lizards Heterodactylus septentrionalis (Figure 2B), Acratosaura spinosa ( Figure 2C) and Enyalius erythroceneus ( Figure 2D). Furthermore, it is possible that the lizards Psilophtalmus sp. (Figure 3A), Mabuya sp. ( Figure 3B) and Eurolophosaurus sp. (Figure 3C), and the snakes Chironius aff. flavolineatus ( Figure 3D), Tantilla sp. ( Figure 3E) and Taeniophallus gr. occipitalis ( Figure 3F), are also undescribed species (Dixon et al. 1993;Adriano. Lima pers. comm. 2010;Alfredo Jr pers. comm. 2010;Freitas 2011). Further studies will be needed to assess the taxonomy of these groups and their geographic distribution and conservation status.
The present work extends the geographic distribution of the snake Trilepida koppesi ( Figure 3G) to the northeast of Brazil and the distribution of the snakes Sibynomorphus neuwiedi ( Figure 3H), Siphlophis leucocephalus ( Figure 4A), Oxyrhopus guibei ( Figure 4B) and Philodryas patagoniensis ( Figure 4C) to the Chapada Diamantina (Freitas and Silva 2007). For this last species this is also the record furthest away from the coast (Freitas 1999;Freitas 2003;Juncá 2005;Lugli and Juncá 2008). Also worth mentioning are the second record for the northeast of Brazil of the snake Chironius quadricarinatus (Figure 4D), and the third record for that same region of the snake Philodryas aestiva ( Figure 4E) (Argôlo 1998;Argôlo and Freitas 2002).
This species list also contains records of the narrowly distributed lizards Gymnodactylus vanzolinii ( Figure 4F), a recently described species, and Tropidurus mucujensis ( Figure 4G), both of which are yet to be recorded outside the Mucugê municipality (Rodrigues 1987;Cassimiro and Rodrigues 2009). Finally, this species list also presents the highest altitude recorded for the snake Bothropoides erythromelas ( Figure 4H), at 1100 m above sea level.
Having basic knowledge of the vertebrate species composition for a given area is crucial if effective conservation strategies are to be designed (Heyer et al. 1994). The number of endemic species and the number of recently described species along with the high probability that other species remain undescribed, support the need for further research on the herpetofauna of the Chapada Diamantina.
In this light, the inventory of the squamate reptiles of the central Chapada Diamantina is an important contribution not only to the knowledge of the region biodiversity but also to its sustainable management. The focus on Mucugê is important given that this municipality makes up more than 60% of the Chapada Diamantina National Park, a conservation unit for which detailed information on herpetofauna is scarce. Nonetheless, it is also important that further attention is devoted to the management of the areas outside protected areas, as the pressure for land use change, namely for agriculture, is increasing.
Finally, this work, the first publication using data collected during fauna inventories undertaken as part of the mitigation measures imposed by the ICMBio, highlights how this and other (e.g. roadkills) less traditional data sources can provide important information on the herpetofauna of a region. The use of these sources could prove to be a cost-effective complement to more traditional survey methods, something of special importance especially in the case of megadiverse countries like Brazil where large areas are yet to be studied and little is known about many species (Freitas et al. 2011).