Anurans from the Taquari River Valley, Rio Grande Do Sul State, Southern Brazil
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Herpetology Notes, volume 7: 693-701 (2014) (published online on 25 November 2014) Anurans from the Taquari River Valley, Rio Grande do Sul State, Southern Brazil Diego Anderson Dalmolin1,*, Eduardo Périco2, Iberê Farina Machado3 and Samuel Renner2 Abstract. The Taquari River Valley region is located in the Atlantic Forest biome and its Anuran diversity has not been sufficiently explored. This survey presents a list of Anuran species registered in five localities in this region. A total of 41 species were reported; 36 species in four scientific collections, nine from literature and 24 from active survey. The presence of eight species endemic to the state of Rio Grande do Sul and 19 endemic to South Brazil is remarkable. Although most of the species are considered “Least Concern”, Melanophryniscus admirabilis is categorized as “Critically Endangered” and Hypsiboas stellae as “Data Deficient”. The species inventory aims to contribute to the knowledge and distribution pattern of Anurans in the state of Rio Grande do Sul (RS). Key words. Amphibians, Araucaria Forest, Atlantic Forest, geographical distribution, inventory Introduction processes such as lineage origin and high speciation coupled with low extinction rates (Villalobos, 2013). The Atlantic Forest is considered one of the richest Amphibians are facing extinction worldwide as a biomes on Earth presenting, as it does, high levels result of numerous factors and anurans are among of endemism (Ribeiro et al., 2009; Vrcibradic et al., the most endangered vertebrate groups due to human 2011; Ouvernay et al., 2012) and is also one of the 34 progress and development (Piatti et al., 2012). A “hotspots” of biodiversity in the world (Mittermeier et strong correlation exists between habitat alteration al., 2004). Historically this biome has been subjected to and loss of biodiversity; however the vulnerability of intense modification of its natural habitats (Montesinos amphibian assemblages may vary in different habitat et al., 2012). Today only 7% of its original area remains types despite habitat alteration (Jongsma et al., 2014). in a highly fragmented system (Junior, 2005). Despite Due to its sensitivity to environmental changes and the continued process of alteration, the Atlantic Forest decline situations, studies which provide information still retains a significant number of species (Morellato about anuran richness and diversity are important and and Haddad, 2000) mainly as a result of historical a requirement for conservation (Kiesecker, 2010; Keith et al., 2014). Rio Grande do Sul is the southernmost portion of the distribution of the Atlantic Forest and its anurofauna was first surveyed in 1867 (Hensel, 1867). Among the most 1 Universidade Federal do Rio Grande do Sul, Programa recent surveys throughout the state (Braun and Braun, de Pós Graduação em Biologia Animal, Laboratório de Herpetologia. Av. Bento Gonçalves 9500, Agronomia, 1980; Garcia and Vinciprova, 1998) and species lists 91501-970, Porto Alegre, RS, Brasil. (Gayer, Gomes and Krause, 1988; Kwet and Di-Bernardo, 2 Centro Universitário UNIVATES, Programa de Pós Graduação 1999; Kwet, 2001; Loebmann, 2005; Loebmann and em Ambiente e Desenvolvimento, Laboratório de Ecologia e Vieira, 2005; Borges-Martins et al., 2007; Deiques et Sensoriamento Remoto. Rua Avelino Talini, 171, 95900-000, al., 2007; Machado and Maltchik, 2007; Colombo et Lajeado, RS, Brasil. al., 2008) there are no references related to the Taquari 3 Universidade Federal de Goiás, Instituto de Ciências River Valley. This is alarming as in recent years the Biológicas, Departamento de Ecologia. Prédio do ICB 1, Campus Samambaia, Laboratório de Herpetologia e Taquari River Valley has received major environmental Comportamento Animal. changes due to its great potential for the construction * Corresponding author – [email protected] of hydroelectric plants (Capeletto and Moura, 2011). 694 Diego Anderson Dalmolin et al. Figure 1. Location map of the Taquari River Valley, Rio Grande do Sul (RS), Brazil. The numbered municipalities correspond to: 1- Arvorezinha (28º51’10”S, 52º18’23”W); 2- Muçum (29º06’56”S, 51º50’59”W); 3- Lajeado (29º26’39”S, 51º57’0”W); 4- Cruzeiro do Sul (29º34’08”S, 52º00’22”W); and 5- Taquari (29º46’35”S, 51º54’29”W). Although little known, the anurofauna Valley contains out and the museums of Universidade Federal do Rio endemic and endangered species of anuran such as Grande do Sul (UFRGS), Pontifícia Universidade Melanophryniscus admirabilis, discovered as recently Católica do Rio Grande do Sul, PUCRS (MCP- as 2004 and described in 2006. In this work, we aim Anfíbios), Zoobotânica Foundation of Rio Grande do to gather and condense the sparse knowledge of the Sul (MCNFZB) and UNIVATES were visited. A listing anurofauna in the Taquari River Valley. of scientific resources used in this study is presented in Appendix 1. Identification of all specimens originating Materials and Methods from municipalities of the Taquari Valley were verified against specific bibliographies (Maneyro and Carreira, Study area 2012; Di-Bernardo, Maneyro and Grillo, 2006). This study was developed in Taquari River Valley, In addition,field visits were made to capture new located in the Center-east of Rio Grande do Sul State specimens in theArvorezinha (28º51’10”S, 52º18’23”W), (Figure 1). The geopolitical region of the Taquari River Cruzeiro do Sul (29º34’08”S, 52º00’22”W), Lajeado Valley (~4,800 km2) is covered by two forest formations (29º26’39”S, 51º57’0”W), Muçum (29º06’56”S, of Atlantic Forest biome; the Seasonal Deciduae Forest 51º50’59”W) and Taquari (29º46’35”S, 51º54’29”W) and the Mixed Ombrophilous Forest. The average annual municipalities of the Taquari River Valley (Figure 1). precipitation is approximately 1,400 mm, the drought These municipalities were chosen due to the absence of season between summer and autumn. The annual mean prior sampling, their economic importance and existing temperature is 19°C and the minimum temperature is < conflicts with hydroelectric developments. 13°C in winter (Maluf, 2000). Sampling methods Data collection The surveys sampled monthly in five temporary and To gather information about the anurafauna occurring permanent wetlands between March 2011 and November in the Taquari Valley, literature surveys were carried 2012. The total sampling time exceeded 180 hours, Anurans from the Taquari River Valley, Southern Brazil 695 with tadpoles sampled during daylight hours and adults In terms of scientific collections, the 37 identified species at night. For tadpoles sampling an open-ended metal were distributed as 18 species in two municipalities at cylinder 70 cm in length and 32 cm in diameter (Alford UFRGS, 26 species in eight districts at MCP-Anfíbios, and Crump, 1982; Rossa-Feres, 1997) was used. At six species in two municipalities at MCNFZB and 13 each site the right, middle and left edges of the wetland species in two municipalities at UNIVATES. In the were sampled. All individuals inside the metal cylinder published scientific record the knowledge of the anuran were removed using a 18 x 10cm dip net with a mesh fauna is scarcer. Scientific surveys and publishing size of 3 mm2.. Sampling was concluded only after 10 began in the 1980s (Braun & Braun, 1980) and returned consecutive sweeps with no tadpole collection. Samples to appear in the scientific community only after a few were immediately anesthetized with benzocaine and decades, specifically with records for endemic frogs of fixed in 5% formaldehyde. The specimens collected the Araucaria forest (Conte et al., 2010), new locations were deposited in the Scientific Collection of Zoology for invasive species Lithobates catesbeianus (Giovanelli, of the University Center UNIVATES. The tadpoles were Haddad and Alexandrian, 2007, Both et al., 2011) and identified using taxonomic keys specific to southern as the descriptions of Hypsiboas poaju (Garcia, Peixoto Brazil (Machado and Maltchik, 2007). and Haddad, 2008), Hypsiboas stellae (Kwet, 2008) and The adult anurans were surveyed by visual and Melanophryniscus admirabilis (Di-Bernardo, Maneyro auditory search procedures between sunset and 24:00 and Grillo, 2006). (Crump and Scott, 1994). Six 10-min transects were sampled in each pond, amounted to 60 min of sampling The total sampling time was 494h, of which 388h was time at each site. Each transect had its starting point allocated to the acoustic and visual adult survey and randomized and points were sequentially distributed 126h to tadpole collection with a dip net (Table 2). By along the length of the ponds. All individuals located the sampling methods of active survey (visual, acoustic visually or acoustically were registered. Pilot studies and tadpoles captures), a total of 24 anuran species have shown that 30 minutes is sufficient time for distributed in six families (Alsodidae, Bufonidae, sampling the largest pond in the area without a record Hylidae, Leptodactylidae, Odontophryinidae and of a unique species. All individuals were identified Ranidae) were observed. While Rhinella icterica according to Cei (1980), Maneyro and Carreira (2012) (100%, five municipalities), Dendropsophus minutus, or Di-Bernardo, Maneyro and Grillo (2006). The Scinax fuscovarius (80%, four municipalities) and capture and preservation of specimens was authorized Physalaemus biligonigerus (60%) were present in the under SISBIO license 31580. highest number of municipalities, 20 other species were present in only one or two municipalities. Sampling of the tadpoles resulted in recording