A new species of freshwater crab of the genus Chaceus Pretzmann, 1965 (Brachyura: Decapoda: Pseudothelphusidae) from La Guajira, including distribution and a key to the species of the genus

Summary: The study introduces a new classification scheme for freshwater crabs of the Americas, the superfamily Pseudothelphusoidea, consisting of two families and eight subfamilies. The new classification shows high congruence with the geographical distribution of species and genera, and is supported by molecular analyses and divergence time estimations associated with geological history.