Revision of the East Mediterranean Orthomus (Coleoptera, Carabidae, Pterostichini), with description of Parorthomus gen. n. socotranus sp. n. from Socotra Island and key to the Old World genera of subtribe Euchroina

The East Mediterranean species of Orthomus Chaudoir, 1838 are revised. The type series of Feronia longula Reiche & Saulcy, 1855, F. berytensis Reiche & Saulcy, 1855, F. proelonga Reiche & Saulcy, 1855, Orthomus longior Chaudoir, 1873, O. sidonicus Chaudoir, 1873, and O. berytensis akbensis Mateu, 1955 were studied and lectotypes for the first four are designated. Also, the following nomenclatural acts are proposed: Feronia proelonga Reiche & Saulcy, 1855, syn. n. of Orthomus berytensis (Reiche & Saulcy, 1855); Feronia elongata Chaudoir, 1859, syn. n. of Orthomus berytensis (Reiche & Saulcy, 1855); Orthomus sidonicus Chaudoir, 1873, syn. n. of Orthomus longior Chaudoir, 1873; Orthomus velocissimus andalusiacus Mateu, 1957, syn. n. of Orthomus velocissimus akbensis Mateu, 1955, new assignment for Orthomus berytensis akbensis Mateu, 1955. As a result, three species of the genus inhabit the East Mediterranean biogeographical region: O. berytensis, O. longior, and O. longulus. A key to these three species is given. O. longior is recorded for Turkey and Syria for the first time. In addition, a new synonymy of two West Mediterranean taxa is proposed: O. szekessyi (Jedlička, 1956), syn. n. of O. balearicus (Piochard de la Brûlerie, 1868), and a new genus and a species are described: Parorthomus gen. n. socotranus sp. n. (type locality: Republic of Yemen, Socotra Archipelago, Socotra Island, Fimihin env., 530 m.a.s.l.). Illustrations of the species dealt with here are provided including external characters, habitus, mentum and submentum, and genitalia are provided. Nine genera of the "African Series" of subtribe Euchroina Chaudoir, 1874 are keyed for the first time. Checklists of the species of Orthomus and of the Old World euchroine genera are given.