Four new species of Astenus (Eurysunius) Dejean, 1833 from Western Anatolia, Turkey (Coleoptera: Staphylinidae, Paederinae)

Four new species of Astenus (Eurysunius) Dejean (Staphylinidae: Paederinae) are described from Western Anatolia, Turkey, and illustrated: Astenus gusarovi sp. n. (Cokelez Mountain, Denizli province), A. orgeli sp. n. (Imambaba Tepesi, Aydin province and Bozdaglar, Izmir province), A. kumlutasi sp. n. (Akdaglar, Kutahya province and Murat Mountain, Usak province) and A. honazicus sp. n. (Honaz Mountain, Denizli province). Additional records and updated distributions are provided for A. occiduus Assing, A. sultanicus Assing, and A. sandiklicus Anlas. Distributions of Eurysunius species in Western Turkey are mapped.