Notocupes vitimensis Ponomarenko, 1966

STRELNIKOVA, OLESYA D. & YAN, EVGENY V., 2021, Redescriptions of beetles of the Notocupes generic complex (Coleoptera: Archostemata: Ommatidae) from the Lower Cretaceous of Buryatia, Palaeoentomology 4 (5), pp. 499-514 : 507-508

Notocupes vitimensis Ponomarenko, 1966

( Figs 8–10 )

Material. Holotype – PIN, 1989/3022, part and counterpart of full body, Baissa locality; Lower Cretaceous.

Diagnosis. Elytra with small rounded cells with black maculae around them. Maximum number of cells per row is 27. Epipleuron narrow, without cells. Last abdominal sternite 2.9 times longer than previous one.

Description. Cuticular tubercles round, evenly distributed, diameter ca. 0.02 mm and density 789 per mm 2 on most regions ( Fig. 9 C-a); larger on terminal abdominal sternite VII, in depressions on sternites III–VI and on metanepisterna, diameter 0.03 mm and density 485 per mm 2 ( Fig. 9 C-b). Distance between smaller tubercles 0.01–0.02 mm. Elytra with three V-shaped transverse darker spots ( Fig. 8A ).

Pronotum:maximum width 2.3 mm; sides not dentate. Pronotal disc with paired rectangular protuberances and median furrow between them.

Prosternum: pleurosternal sutures more or less straight; notopleural sutures diverging posteriorly. Propleuron narrowing anteriorly, more or less triangular.

Scutellar shield: not preserved.

Elytra: with rounded cells; cells missing in field I, other fields with two rows; field II only partially preserved; fields III and IV with about 27 cells, field V with 23, field VI with 24, and field VII with 3. Number of cell rows 10. Elytral cells with black maculae, with numbers varying from 4 to 7. Fields IV and V usually with 5 maculae, but cells closer to elytral base and areas around converging veins with only 4; more than half of cells at elytral midlength with 6 maculae, and some around area of elytral maximum width with 7. Usually, cells with increased number of maculae (6–7) surrounded by 4-maculae cells. Field VI, near elytral base (first 6 cell pairs), with cells with 5 maculae, next 4 pairs of cells with 6 maculae, and up to 7 maculae at elytral midlength. Field VII with two cells with 4 maculae and one cell with 5. Cells occupy more than half distance between veins and often reach lateral margins of fields, resulting in zigzag pattern of veins. Elytral length/width ratio 3.3, elytra slightly extending beyond abdominal apex posteriorly. Veins 2 and 3 with common stem; veins 2 slightly curved, but not following shape of epipleural margin. Vein 3 slightly curved near elytral apex; veins 4 and 5 merge three cells anterior to apex, and vein 3 merges with them three cells posterior to this site; vein 2 reaches elytral apex. Elytron with maximum width at midlength. Epipleural margin curving slightly towards apex. Epipleuron narrow, not narrowing at basal third but then gradually narrowing towards apex. Epipleural width near elytral base/epipleural width near elytral apex ratio 3.4. Elytral base and apex rounded. Humeral bulge not prominent. Elytral width/pronotal width ratio 2.

Metaventrite: length around 1.4 mm, width at posterior margin 2.6 mm, on anterior margin 0.9 mm. Width of posterior margin of metaventrite/anterior margin ratio 2.9; width of posterior margin/length ratio 1.8.

Abdomen: relief of sternites very prominent. Apical sternite VII and depressed portions of sternites III–VI with sculpture of large tubercles. Abdomen narrowing posteriorly starting from sternite VI, with pointed apex formed by sternite VII. Length ratio of sternites 1.7:1:1:1:2.9. Apical sternite VII with width to length ratio 1.5.

Legs: procoxae transverse, with protruding, anterolaterally oriented protrochantins, located close to posterior pronotal margin. Mesocoxae rounded, narrowly separated. Metacoxae 1.8 times wider than long.

Measurements. Elytral length— 8 mm, width— 2.4 mm.

Remarks. Paired rounded tubercles in front of the posterior pronotal margin were mentioned in the original description ( Ponomarenko, 1966a). They are now reinterpreted as visible outlines of the procoxаe. Rounded furcal pits are visible in front of them ( Fig. 8C—f.p ., see DuPorte, 1965;fup.; Friedrich et al.,2009).Most species of the Notocupes complex have contiguous coxae, although species with separated coxae have also been described ( Soriano & Delclòs, 2006). The presence of an intercoxal process in Amblomma species was the main character to separate them from Notocupes . However, in some species this character is not visible, and was suggested to be excluded from the diagnosis ( Kirejtshuk, 2010). As this character is not visible in specimens of the type series of N. vitimensis , it is still a topic for discussion.

Figures

FIGURE 8. Counterpart of Notocupes vitimensis (PIN, 1989/3022). A, Wetted with 95% ethanol. B, Dry. C, Interpretative line drawing, ventral aspect. Abbreviations: cx1, coxa1; f.p., furcal pit.

FIGURE 9. Notocupes vitimensis (PIN, 1989/3022). A, Interpretative line drawing, dorsal aspect (grey filling indicates elytral color pattern). B, Counterpart wetted with 95% ethanol (rectangle indicate area within C photograph). C, Details of elytral cells. D, Scheme of the distribution of cells and tubercles on the elytra (numbers indicate quantity of tubercles around cells).All pictures are mirrored.

FIGURE 10. Interpretative line drawing of elytra of Notocupes vitimensis. A, Left elytra. B, Mirrored right elytra. C, Mirrored left elytra of counterpart. D, Right elytra of counterpart. E, General scheme of elytra of Notocupes vitimensis.