Chiasmocleis carvalhoi Cruz , Caramaschi & Izecksohn , 1997 ( Anura : Microhylidae ) : Distribution extension in São Paulo state , southeastern Brazil , and geographic distribution map

Herein, we report new records for Chiasmocleis carvalhoi from southern regions of São Paulo state. We also provided an updated geographic range map and modelled the potential distribution of this species. New records extended the known species distribution about 150 km southwards of the São Paulo state coast. Moreover, the geographic range map of C. carvalhoi and its potential distribution evidenced that the distribution of this species is typical to lowlands forests habitats and reinforce its current endangered conservation status. DOI: 10.15560/10.5.1243 Figure 1. Adult male of Chiasmocleis carvalhoi (SVL= 18.38 mm) from Itanhaém municipality, São Paulo state, Brazil. Photo by: Amom M. Luiz

Moreover, we provided an update geographic range map and modelled the potential distribution of this species based on the new records, literature, and museum-based data from "Coleção de Anfíbios Célio F. B. Haddad (CFBH)", and "Museu de Zoologia Adão José Cardoso", Universidade Estadual de Campinas (ZUEC).We choose these scientific collections due to their well-organized database with an excellent rate of sampling in the studied area, and due to our logistical constraints to sample other scientific collections.However, we are aware of the records equally relevant from other scientific collections (e.g., MNRJ) and which are absent of our data.
On 16 December 2011, around 22:00 h during a fieldwork in a private ownership, at municipality of Itanhaém, southern coast of São Paulo state (24°11′1.9″S, 46°51′44.2″W; 20 m a.s.l.), we found three males (mean Chiasmocleis is the most species-rich genera of Microhylidae with 29 assigned species, being widely distributed throughout the Neotropical region (Cruz et al. 1997;Frost 2014).In the South America, Chiasmocleis species are associated with the Amazon Forest, open areas of Brazilian savannas, the Chaco region, including Bolivia and Paraguay, and throughout the Atlantic Forest (Caramaschi and Cruz 1997;Frost 2014).Currently, eleven species of Chiasmocleis are assigned to the Atlantic Forest (Frost 2014), including the central humming frog C. carvalhoi.
Chiasmocleis carvalhoi (Figure 1) is a small sized species (SVL 15.0-22.0mm) and is diagnosed by: hands and feet not webbed, finely marbled belly, and smaller size than other Atlantic Forest Chiasmocleis species (maximum SVL = 18.3 mm in males and 22.5 mm in females; see Cruz et al. 1997) described from municipality of Seropédica, Rio de Janeiro state (Cruz et al. 1997).Chiasmocleis carvalhoi lives on the leaf-litter of lowland Atlantic Forest (up to 40 m above sea level (a.s.l.)), breeding after heavy rains as an explosive breeder (Cruz et al. 1997).Males can be found calling on the edges or floating in the earlyformed temporary ponds inside the forest (Izecksohn and Carvalho-e-Silva 2001;Pimenta and Peixoto 2004;Wogel et al. 2004).Pimenta et al. (2002) provided the first record from Bahia state, northeastern Brazil.Recently, records from Espírito Santo state were provided (Almeida et al. 2011), filling a gap between seemly disjoint populations of this species (Pimenta and Peixoto 2004).The known southward limit of its distribution is the Ubatuba municipality on the northern coast of São Paulo State (Hartmann et al. 2002).
Herein, we report new records for Chiasmocleis carvalhoi from southern regions of São Paulo state.Cruz, Caramaschi & Izecksohn, 1997 (Anura: Microhylidae) Abstract: Herein, we report new records for Chiasmocleis carvalhoi from southern regions of São Paulo state.We also provided an updated geographic range map and modelled the potential distribution of this species.New records extended the known species distribution about 150 km southwards of the São Paulo state coast.Moreover, the geographic range map of C. carvalhoi and its potential distribution evidenced that the distribution of this species is typical to lowlands forests habitats and reinforce its current endangered conservation status.(MZUSP 153445-153449).We also recorded a specimen (CFBH 23711; collected by Ricardo Sawaya, Fausto Barbo, and Murilo Guimarães on 1 October 2011; Figure 2) at Ilha do Ameixal, Peruíbe municipality, southern coast of São Paulo state (24°25′28.46″S, 47°4′52.84″W; 18 m a.s.l.).These records represent the southernmost known localities of geographic range of C. carvalhoi, and extend its known geographic range for about 230 km from the last published record (Ubatuba municipality; Hartmann et al. 2002).Figure 3 shows the known occurrence points, new records, and potential distribution based on species distribution modeling (SDM).The potential distribution was modeled using 114 records compiled from literature data, voucher specimens and new records.

Chiasmocleis carvalhoi
The potential distribution of C. carvalhoi modeled by Maxent (Phillips et al. 2006) based on occurrence records analyzed and the 19 bioclimatic variables (Hijimans et al. 2005) shows that this species is constrained to lowlands.In fact, its occurrence seems to be strongly associated to lowlands forest environments, such as "restinga" habitats, mainly in São Paulo and Rio de Janeiro states (Figure 3)."Restinga" habitats are described as the quaternary sediments deposited during oceanic transgressions and regressions (Suguio and Tessler 1984).Moreover, this term can be used to designate a complex of vegetal physiognomic forms (i.e., fields, scrubs, and forests), generating a gradient from the so called restinga fields to restinga forests, established on sandy soils along the Brazilian coast plains (Cerqueira 2000; but see Marques et al. 2011).However, as cited here, Pimenta and Peixoto (2004) recorded disjunct populations of C. carvalhoi in the southern part of the state of Bahia in eastern Brazil.In fact, these populations may possibly occur in the "mussunungas"  habitats.As are the "restinga", the "mussunungas" also are habitats associated with Atlantic rainforest biome, and occurs from southern Bahia and northern Espírito Santo states.This habitat can be defined as a physiognomy that ranges from grasslands to woodlands, which grows over sandy spodosol soils, originated from sandstones of the Barreiras Group from the Tertiary period (ca.16 million years before present) (Saporetti-Junior et al. 2012).Thus, "mussunungas" habitats seem to be very similar to "restinga" habitats and the former can represent a potential occurrence distribution of C. carvalhoi based on our SDM for the species.
The International Union for Conservation of Nature (IUCN) listed Chiasmocleis carvalhoi as endangered, based on restricted area occupancy, distribution severely fragmented and probable declining of its habitat quality (Pimenta and Peixoto 2004).Therefore, although our records had extended the known distribution of this species, its endangered and restricted habitat, including São Paulo state, are concerns to take account in the conservation of Chiasmocleis carvalhoi and other typical species from restinga forests.This is the case for other anuran species inhabiting restinga forests in the São Paulo state (e.g., Arcovomer passarelli; Malagoli et al. 2012).Restinga habitats are one of the most endangered physiognomic forms of the Atlantic rainforest (Marques et al. 2011), and consequently, species restricted to and strongly associated with these habitats are prone to severe population declines, as evidenced by the conservation status of Chiasmocleis carvalhoi.Distributional data are primary to inform conservation planning and reinforce the concerns about necessity of creation of new conservation units in restinga habitats (Rocha et al. 2008).

Figure 3 .
Figure 3. Geographic distribution map and potential distribution of Chiasmocleis carvalhoi.Circles represent points of occurrence.Black circles represent known records from literature and scientific collections, and blue circles represent new records.The SDM was computed in MaxEnt 3.3.3(Phillips et al. 2006), using 19 bioclimatic variables at spatial resolution of 30″ (Hijmans et al. 2005) and 114 records.AUC value was 0.998 which indicated a model with better performance than expected by chance (see Elith et al. 2006).