Abstract

Araripenepa vetussiphonis gen. et sp. nov., the oldest representative of the family Nepidae is described from the Early Cretaceous Crato Formation in Brazil. It is considered as the sister group of all the extant Nepidae, having retained tarsi with three tarsomeres and a transverse pronotum. The general habitus, elongate siphon, and strong grasping legs strongly suggest that its biology was very similar to that of the extant Nepa spp., viz. a predaceous bug living in the mud and/or the abundant aquatic vegetation of the Crato palaeolake. Possibly, the Triassic—Jurassic representatives of the stem group of Nepidae had no elongate siphon and were similar to Cratonepa, an enigmatic Nepoidea previously described from the Crato Formation. The development of the siphon was possibly favoured by the diversification of the lacustrine plants that occurred during the Early Cretaceous.