Olkasuchus
Olkasuchus is an extinct genus of desmatosuchine aetosaur known from the Late Triassic Los Colorados Formation of northwestern Argentina. The genus contains a single species, Olkasuchus walasto, known from a partial skeleton with preserved osteoderms.
Discovery and naming
The Olkasuchus holotype specimen, PULR-V 246, was discovered in outcrops of the upper Los Colorados Formation within Talampaya National Park in La Rioja Province, Argentina. The specimen comprises an incomplete, partially articulated skeleton including vertebrae, ribs, a partial right scapulocoracoid, humerus, pelvic girdle, femur, tibia, and fibula. Several osteoderms are preserved from the dorsal, ventral, sacral, and caudal regions.In 2025, Juan C. Sotomayor and colleagues described Olkasuchus walasto as a new genus and species of desmatosuchine aetosaurs based on these fossil remains. The generic name, Olkasuchus, combines ólka, a word from the now-extinct Kakán language spoken by the native people who inhabited the type locality region, meaning "red", with the Greek word soûkhos, derived from the Greek name of Sobek, the crocodile-headed deity of Ancient Egyptian myth. This refers to the red-colored outcrops of the Los Colorados Formation in which the holotype was found. The specific name, walasto, is a Kakán word meaning "corner", referencing the type locality of La Esquina, which is in turn a Spanish word for "corner".