First fossil species of ship-timber beetles (Coleoptera, Lymexylidae) from Eocene Rovno amber (Ukraine)

A new lymexylid fossil species, †Raractocetus sverlilo Nazarenko, Perkovsky & Yamamoto, sp. nov., is described from late Eocene Rovno amber of Ukraine. This new species is similar to species of the recent genera Atractocerus Palisot de Beauvois and Raractocetus Kurosawa in the ship-timber beetle subfamily Atractocerinae, but differs in pronotal and elytral features. Notably, the new species is one of the smallest atractocerines known to date. This is the first member of the family Lymexylidae found in Rovno amber. Our finding sheds further light on the paleodiversity of atractocerine beetles, highlighting a peculiar distribution during the Eocene. Only one extant atractocerine specimen has been reported from Europe (Greece), while three species from Eocene European amber forests with equable climate are known now, including two species from the otherwise tropical genus Raractocetus. Our finding of the Raractocetus beetle from Rovno amber is of significant biogeographically because it indicates the wide distribution of the genus in the Eocene European amber forests.