Diversity of rove beetles (Coleoptera: Staphylinidae) in Early Cretaceous Spanish amber

Twenty specimens of Staphylinidae (Coleoptera: Polyphaga) were found in the Early Cretaceous Spanish amber. Two new genera and four new species are reported in these samples: Cretasonoma corinformibus in the supertribe Faronitae, and Penarhytus tenebris in the supertribe Pselaphitae, both in the subfamily Pselaphinae; Prosolierius parvus in the subfamily Solieriinae; and Kachinus magnificus in the subfamily Scydmaeninae. Both Prosolierius and Kachinus exemplify the similarity between Cretaceous Spanish amber and Cretaceous Lebanese and Burmese amber, despite their different ages. Pselaphinae is the most common rove beetle subfamily in amber inclusions worldwide, their small size and cryptic litter-dwelling perhaps make them susceptible to being trapped by resin and conserved. Kachinus magnificus, reported in six of the Scydmaeninae specimens from Spanish amber, is the oldest species formally described for the subfamily. Penarhytus tenebris and Prosolierus parvus come from the Peñacerrada I amber deposit, Kachinus magnificus from the El Soplao amber deposit, and Cretasonoma corinformibus is found at both locations, in the Basque-Cantabrian Basin, on the northern Iberian Plate (today the Iberian Peninsula).