Decapod Crustacea from the Agrio Formation (Lower Cretaceous) of the Neuquén Basin, Argentina

AGUIRRE-URRETA, M.B.; LAZO, D.G.; RAWSON, P.F.

PALAEONTOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2012 vol. 55 p. 1091 - 1103

0031-0239

Two taxa of fossil decapod crustaceans are newly recorded from the Agua de la Mula Member of the Agrio Formation (Upper Hauterivian-Lower Barremian) of the Neuquén Basin of west-central Argentina, Astacodes falcifer Bell and a new species of Palaeohomarus, P. pacificus. The preservation of the specimens is very good, some showing compound eyes and a stridulatory apparatus, features rarely found in fossils forms. Many specimens are preserved articulated inside calcareous nodules, within black shales. The sediments accumulated in a low-energy marine environment and diagenetic mineralization occurred very rapidly, prior to significant decay. Palaeohomarus was a rare genus in the Cretaceous with a palaeogeographic distribution restricted to the Mediterranean Tethys, the eastern USA and Madagascar while Astacodes falcifer is recorded only from Speeton (eastern England) and Neuquén.