Aegla chilota, new species of anomuran freshwater crab from Chiloé Island, western Patagonia

Abstract

Abstract We describe a new species of freshwater crab, Aegla chilota, from two small streams at Yaldad Bay, in the southern end of Chiloe Island, western Patagonia. The new taxon is distinguished from the remaining Chilean species of Aegla Leach, 1820 by the following morphological diagnostic features: rostrum neatly triangular, short, scarcely surpassing eyes; orbital sinus wide, shallow, limited by tiny extra-orbital spine and wide extra-orbital sinus; carpal lobe prominent, triangular, tipped by at least two coalescent acute conical scales; second abdominal epimeron little produced, armed with acute scale; telson plate roughly pentagonal, with functional median suture. Molecular phylogenetic analyses also support the separation and diagnosis of A. chilota from its sister taxon, A. hueicollensis Jara and Palacios, 1999. The type locality for A. chilota n. sp. is a small river that drains a small hilly portion of the south-eastern coast of Chiloe Island; the other river in which the species was found is isolated from the type locality by the Yaldad Bay into which both rivers drain.