Acanthochelys macrocephala (Rhodin, Mittermeier, and McMorris 1984) – Big-Headed Pantanal Swamp Turtle, Pantanal Swamp Turtle

Abstract

The big-headed Pantanal swamp turtle, Acanthochelys macrocephala (Family Chelidae), is a medium-sized aquatic turtle (carapace length to 295 mm), endemic to the Pantanal and Chaco ecoregions of Brazil, Bolivia, and northern Paraguay. It has a limited distribution in the upper Ro Paraguai drainage and is apparently restricted to the swampy lowlands of the Pantanal and the arid plains of the northern Chaco. The species inhabits marshes, wetland areas, shallow bays and brackish lagoons (salinas), as well as opportunistically utilizing ephemeral waterbodies, including roadside drainage ditches and farm irrigation reservoirs and artificial ponds in pasturelands (tajamares). Population levels appear relatively robust at present and the species is not uncommon, but ongoing patterns of habitat loss in the Chaco, combined with climate change leading to increased aridity and threat to ephemeral water resources potentially threaten the species, and it is currently categorized as Near Threatened on the IUCN Red List.