Bukhkalius Kirejtshuk & Jarzembowski, 2020

Li, Yan-Da, Huang, Di-Ying & Cai, Chen-Yang, 2021, Revisiting the morphology and systematic placement of the enigmatic Cretaceous ommatid beetle Bukhkalius lindae (Coleoptera: Archostemata: Ommatidae), Papéis Avulsos de Zoologia 61, pp. 1-6 : 2

Genus Bukhkalius Kirejtshuk & Jarzembowski, 2020

Type species: Tetraphalerus lindae Jarzembowski, Wang & Zheng, 2017 .

Revised diagnosis: Body elongate. Head moderately elongate; temples short; antennal grooves short, only reaching anterior margin of eyes; antennae short, subfiliform; separate mentum present. Pronotal disc without protuberances or ridges; propleura not reaching anterior prothoracic margin; procoxae contiguous. Elytra with indistinct longitudinal ridges (primary veins); lateral edge of elytra with double rows of teeth. Abdominal ventrites abutting.

Bukhkalius differs from Tetraphalerus in head only moderately elongate, antennal grooves incomplete, and mushroom-shaped micro-tubercles absent. Bukhkalius differs from the remaining genera in Ommatidae in the combination of antennal grooves present (though incomplete), separate mentum present, and propleura not reaching anterior prothoracic margin.

Remarks: The diagnosis provided in Kirejtshuk(2020) was insufficient, which cannot really differentiate Bukhkalius from Omma and Omma -like genera. For example, he claimed that “this new genus [ Bukhkalius ] differs from the genera with subglobous prothorax ( Cionocoleus, Cionocups , Omma, Polyakius and Rhopalomma ) in the clear ‘neck’ of the head”. However, neck is clearly present in both extant (Escalona et al., 2020) and fossil ommatines. The neck in some fossil Omma ( Figs. 4B, C ) could be even narrower than that of Bukhkalius .

Figures

Figure 4. Head of fossil Omma species from Burmese amber, showing the well-defined neck region. (A) Omma lii, holotype, NIGP164898. (B) Omma sp. 1. (C) Omma sp.2. Scale bars:500 μm.