A description of the first instar larva of Promecognathus Chaudoir (Coleoptera: Carabidae)

The first instar larva of Promecognathus laevissimus (Dejean) is described, representing the first species of Promecognathus known in the larval stage. The larva is autapomorphic in having: (1) additional setae, often in great number, on many sclerites of the body, (2) a transverse, not bulbous, sensory area located ventrally and laterally at the apex of antennomere III, and (3) the marginal area of the mesonotum, metanotum and abdominal tergites I-VI more expanded than usual in carabid larvae. No evidence was found from the larval morphology of P.laevissimus to indicate the sister group of the Promecognathini.