Adelidium Tillyard, 1918

Nabozhenko, M. V. & Bukejs, A., 2021, A new species and a key to Isomira Mulsant, 1856 (Coleoptera: Tenebrionidae: Alleculinae) from Eocene Baltic amber, Caucasian Entomological Bulletin (Caucas. entomol. bull.) 17 (1), pp. 51-56 : 55

Adelidium Tillyard, 1918

Type species: Adelidium cordatum Tillyard, 1918 by original designation [ Tillyard, 1918: 752]. Monotypic genus.

Type stratum. New South Wales, Australia, Glenlee railway cutting, Anisian, Middle Triassic (247–242 Ma) .

This genus was included in the family Tenebrionidae without any comparison with tenebrionid taxa. Tillyard [1918] suggested that A. cordatum possibly closely related to some Ademosyne Handlirsch, 1906 (Archostemata: Ademosynidae ) from the Upper Triassic Ipswich Coal Measures (Queensland, Australia). In fact, characters of wide and very convex single elytron of Adelidium with eight or nine visible striae without scutellary striole can be interpreted very widely. The taxon distinctly does not belong to the family Tenebrionidae , which is known reliably only from the Late Jurassic. Adelidium cordatum specially was not included in the fossil records [Kirejtshuk at al., 2008; Kirejtshuk, Ponomarenko, 2018; Nabozhenko 2019]. However Bao and Antunes-Carvalho [2020] still wrote that it is Tenebrionidae . Here we propose to interpret Adelidium cordatum as Coleoptera incertae sedis.