To be or not to be a synonym - revision of the - complex (Coleoptera, Chrysomelidae, Donaciinae).

The East Palaearctic species Jacobson, 1906 and Goecke, 1944 have been confused for decades. Finally, was synonymized with by Askevold (1990) but he could not examine the type series of because it was stored in an inaccessible collection. Cong and Yu (1997) re-established as a distinct species, also without direct access to the type series. The synonymization by Askevold (1990) was applied in the identification key of Palaearctic Chrysomelidae (Warchalowski 2010) and the Catalogue of Palaearctic Chrysomelidae (Silfverberg 2010). Because the type series of is now accessible, it has been possible to proof that is a distinct species, and a lectotype has been established from the series of seven syntypes. Chen, 1966 and Chen, 1966, which were split from the mixture of and , are now also synonymized with , because their characters are the same or within the variation range of the characters of Furthermore, a distribution map is provided with the reliable records known to date.