Key to subgenera of the genus Adelostoma Duponchel, 1827

1 Epipleural carina complete, extending from apex of elytra up to humeral angle (sensu Koch 1952: 5, Fig. 2). Apical margin of buccal fissure lobes truncate............................................................................ 2

- Epipleural carina developed only apically, extending forwards from apex of elytra roughly to level of penultimate or third abdominal ventrite (sensu Koch 1952: 5, Fig. 4; 23, Fig. 94). Apical margin of buccal fissure lobe subtriangulate or subdentate................................................................................................... 3

2 Prothorax with foliaceous lateral portions, with antennal sulcus on hypomeron. Antennomeres closely fitted into one another, apical margin of the tenth antennomere angulate.................................... subg. Psaryphulum Koch, 1952

- Prothorax without distinctly foliaceous lateral portions, without antennal sulcus. All antennomeres distinctly pedunculate, apical part of the tenth antennomere straight-truncate........................... subg. Adelostoma s.str. Duponchel, 1872

3 Dorsal surface covered with long erect or semi-erect setae. Antennomeres IV-IX transverse or at most subquadrate. Anterior margin of pronotum slightly or moderately emarginated; sides roughly and irregularly denticulate; dorsal surface covered with net-like sculptures. Space between coarse and deep punctures on reflected portion of elytra smaller than their diameter................................................................ subg. Zarudnionymus Semenov & Bogatchev, 1947

- Dorsal surface glabrous without any setae. Antennomeres IV-IX distinctly longer than wide. Anterior margin of pronotum deeply emarginated; sides finely and more or less regularly denticulate; dorsal surface without net-like sculptures. Space between coarse and deep punctures on reflected portion of elytra much bigger than their diameter.................................................................................................. .. Omandelostoma subgen. nov.