Are Orthotrichum and Dorcadion (Orthotrichaceae, Bryophyta) heterotypic generic names?

The generic name Dorcadion Adans. ex Lindb. is a superfluous and illegitimate name for Orthotrichum Hedw. The new generic name Dorcadionella Plášek, Sawicki & Ochyra is proposed for a segregate of Orthotrichum which comprises species with superficial stomata that are always monoicous and only occasionally produce gemmae on leaves. Dorcadionella affinis (Schrad. ex Brid.) Plášek, Sawicki & Ochyra is selected as a type of this new generic name. The genus Dorcadionella consists of 63 species and one variety that have a worldwide distribution. Traditionally, they were all placed in Orthotrichum and the relevant transfers to the new genus are effected in the present account.