New records and distribution extension of Acanthochelys macrocephala (Rhodin, Mittermeier & McMorris 1984) in midwestern Brazil

Abstract

The big-headed Pantanal swamp turtle Acanthochelys macrocephala (Rhodin, Mittermeier & McMorris, 1984) is a rare and poorly studied medium-sized freshwater turtle (Rhodin et al., 2021), whose individuals can explore a wide variety of habitat types. Acanthochelys macrocephala has a geographical distribution restricted to central South America. In Brazil, records are restricted to the Upper Paraguay river basin, throughout the Pantanal wetlands or nearby Chaco areas. These records were limited until now to four municipalities of Mato Grosso do Sul and two municipalities of Mato Grosso. Some of the records we provided here constitute the first occurrence of the species for the municipalities of Barão de Melgaço, Nossa Senhora do Livramento, Cuiabá, and Acorizal, and increase from two to six the number of municipalities where the species is currently known in Mato Grosso (previously known for Poconé and Cáceres - the latter being the species type locality).