Elachistocleis corumbaensis, Piva et al., 2017

Novaes-E-Fagundes, Gabriel, Lyra, Mariana L., Loredam, Vinicius S. A., Carvalho, Thiago R., Haddad, Célio F. B., Rodrigues, Miguel T., Baldo, Diego, Barrasso, Diego A., Loebmann, Daniel, Ávila, Robson W., Brusquetti, Francisco, Prudente, Ana L. C., Wheeler, Ward C., Orrico, Victor Goyannes Dill & Peloso, Pedro, 2023, A tale of two bellies: systematics of the oval frogs (Anura: Microhylidae: Elachistocleis), Zoological Journal of the Linnean Society 197, pp. 545-568 : 561

The (mysterious) status of Elachistocleis corumbaensis

Unfortunately, we have no samples confidently assignable to E. corumbaensis . We have two samples from two localities near (around 20 km and 80 km) but not from the type locality of the species (Parque Municipal de Piraputangas, Corumbá municipality; Piva et al., 2017) ( Fig. 3 ). For one of these tissue samples (CFBHT 00078), we were unable to find the voucher specimen. The other (MAPT 1363) was identified by the collectors as E. matogrosso (see: Koroiva et al., 2020). So we assume, albeit tentatively, that it has an immaculate venter. Both samples fall with E. bicolor in our species delimitation ( Fig. 1 ). However, E. corumbaensis was described as having a maculate belly ( Piva et al., 2017). The closest locality that we have a sample of a maculate-bellied species ( E. cesarii ) is Campo Grande, state of Mato Grosso do Sul, Brazil, 357 km from the type locality of E. corumbaensis . It is also worth remarking that E. corumbaensis has several similarities with E. haroi , particularly the dorsal pattern with a dark mark in the shape of a pine tree ( Pereyra et al., 2013; Piva et al., 2017). Our closest sample of E. haroi is from Puerto Carmelo Peralta, Department of Alto Paraguay ( Paraguay), 275 km south of the type locality of E. corumbaensis . For the moment, we consider E. corumbaensis a valid species, although it is unclear if this species belongs to the E. bicolor group or to the E. surinamensis group.

The (unresolved) status of Elachistocleis erythrogaster

This species is apparently restricted to the Centre of Research and Nature Conservation Pró-Mata, state of Rio Grande do Sul, above 900 m a.s.l. ( Kwet & Di-Bernardo, 1998). It was distinguished from E. bicolor [treated as E. ovalis in Kwet & Di-Bernardo (1998)], which occurs in sympatry, by the unique red belly, larger size and other bioacoustic and reproductive characteristics ( Kwet & Di-Bernardo, 1998). We have sampled some individuals from localities close to the type locality – although from the lowland – and they all fall with E. bicolor . This species has not been collected for nearly 20 years and is considered to be rare ( Kwet et al., 2010).

Figures

Figure 1. Species delimitation in Elachistocleis. The tree shown is from the maximum likelihood (ML) analysis with only 16S + COI from only Elachistocleis samples (tree rooted in E. araios). Numbers on branches are SH-aLRT/UFBoot support values. Asterisks represent support above 80/95. The terminals of the tree are named as: original labelling of

Figure 3. Geographic location of sampled specimens (symbols) and type-localities of the nominal species (numbers). 1, Elachistocleis araios; 2, E. bicolor (here illustrated as the city of Buenos Aires; see Discussion); 3, E. bumbameuboi; 4, E. carƲalhoi; 5, E. cesarii; 6, E. corumbaensis; 7, E. erythrogaster; 8, E. haroi; 9, E. helianneae; 10, E. magna; 11, E. matogrosso; 12, E. muiraquitan; 13, E. nigrogularis; 14, E. panamensis; 15, E. pearsei; 16, E. piauiensis; 17, E. sikuani; 18, E. skotogaster; 19, E. surinamensis; 20, E. surumu; 21, E. tinigua.