Rediscovery of Aeglid Crabs in the Rio Jejuí Watershed, Paraguay

Aegla are endemic to southern South America and have been documented in Argentina, Bolivia, Brazil, Chile, Paraguay, and Uruguay. Documentation in Paraguay is sparse, with the last published encounter occurring in 1985; in 1999, the genus was proposed extinct within that country. Since then, a few individual aeglids have been found scattered throughout the Rio Tebicuary watershed. In 2009, aeglids were discovered within the Rio Jejui watershed within eastern Paraguay; males and ovigerous females were successfully captured including a female carrying more than 20 juveniles beneath its pleon. All individuals from the 2010 field season were later identified morphologically as Aegla platensis Schmitt, 1942. This discovery comes after a two-decade gap in abundant aeglid collections within Paraguay and serves as the first recorded breeding population of aeglid crabs to be documented.