title: The riffle beetles (Coleoptera: Elmidae) of the Eocene Baltic amber: Heterelmis groehni sp. nov. and Heterlimnius samlandicus (Bollow, 1940) comb. nov.
abstract: The Eocene elmid beetles known from Baltic amber so far are reviewed, and their natural environment is discussed. Palaeoriohelmis samlandica Bollow, 1940 is re-described based on examination of the holotype. The genus Palaeoriohelmis Bollow, 1940 is synonymized with Heterlimnius Hinton, 1935, and Palaeoriohelmis samlandica is transferred to Heterlimnius (H. samlandicus comb. nov.). Heterelmis groehni sp. nov. is described and illustrated. Elmadulescens rugosus Peris, Maier & Sánchez-García, 2015 from Cretaceous Spanish amber is removed from Elmidae.
authors.affiliation: Institute of Life Sciences and Technologies, Daugavpils University, Vienības 13, Daugavpils, LV-5401, Latvia.; Email: carabidae@inbox.lv.
authors.forename: Andris
authors.initials: A
authors.lastname: Bukejs
authors.affiliation: Department of Zootechny, FGBOU VPO "Kaliningrad State Technical University", Sovetsky av. 1, 236000 Kaliningrad, Russia.; Email: alekseew0802@yahoo.com.
authors.forename: Vitalii I
authors.initials: VI
authors.lastname: Alekseev
authors.affiliation: Vienna Natural History Museum, Burgring 7, A-1010 Wien, Austria.; Email: manfred.jaech@nhm-wien.ac.at.
authors.forename: Manfred A
authors.initials: MA
authors.lastname: Jäch
mesh_terms: D018647:Amber; D000818:Animals; D001517:Coleoptera / Q000033:anatomy & histology* / Q000145:classification; D005580:Fossils
chemical_list: D018647:Amber