Thanatoplagia Alekseev et Bukejs, 2024

ALEKSEEV, VITALII, MCKELLAR, RYAN C. & BUKEJS, ANDRIS, 2024, A revision and addition to Zopheridae (Coleoptera: Tenebrionoidea) in Baltic amber: possible connections between modern Holarctic distributions and Eocene ‘ amber forests’, Zootaxa 5536 (2), pp. 201-247 : 224

Genus Thanatoplagia Alekseev et Bukejs gen. nov.

Type species: Thanatoplagia tamutisi Alekseev et Bukejs sp. nov., designated herein

Taxonomic assignment. The specimen under study belongs to the tribe Sarrotriini based on the combination of the following characters: (1) dorsally concealed antennal insertions; (2) antennae setose, stout, 10- or 11-segmeneted, without clearly separated antennal club; (3) antennal insertions distant from eyes; (4) procoxal cavities open posteriorly; (5) all tarsi tetramerous, not dilated; and (6) metacoxae separated by intercoxal abdominal process rounded apically.

Differential diagnosis. The tribe Sarrotriini includes three extant genera from the Western Palearctic: Diplagia Reitter, 1882 , Orthocerus Latreille, 1796 , and Helioctamenus Schauffuss ( Ślipiński & Schuh 2008) . Despite the apparent similarity, we conclude that the studied fossil cannot be attributed to any of these genera, and thus we propose a new genus for this fossil beetle. Thanatoplagia gen. nov. clearly differs from Diplagia in lacking interfacetal setae, but possessing sparsely setose antennae, and pronotum distinctly narrower than elytral base; differs from Orthocerus in antennal structure (gradually widened towards apex, not fusiform, sparsely and shortly setose in the new genus); and it differs from Helioctamenus in having stout and strongly transverse antennomeres 4–9, and pronotum with three distinct impressions (two oval transverse, shallow impressions laterobasally and one large, rounded impression anteromedially). The new fossil genus differs from other similar sarrotriines in a well-developed antennomere 11 (as long as antennomere 10), pronounced humeri and developed metathoracic wings.

Etymology. The name of the new genus is a compound word and combines the old Greek word θάνατος (thánatos, death) and the old Greek word πλαγία (plagía, slope or hillside) referring to Diplagia , the extant genus of the tribe Sarrotriini . The gender is feminine.

Description. The new genus is monotypic. Therefore, the generic description considerably overlaps that of the type species.