Notocupes laticella Ponomarenko, 1969

STRELNIKOVA, OLESYA D. & YAN, EVGENY V., 2023, Redescriptions of the Triassic Notocupes beetles (Archostemata: Ommatidae) from Kyrgyzstan and South Kazakhstan, Palaeoentomology 6 (2), pp. 174-190 : 177-180

Notocupes laticella Ponomarenko, 1969

( Figs 1–3 )

Notocupes laticella Ponomarenko, 1969: 90 .

Material. Holotype and five paratypes, parts and counterparts of almost complete bodies PIN 2240 /6, 71, 74, 2555/1662, 1686.

Holotype. PIN 2555 /1663, part and counterpart of almost complete body, Dzhayloucho locality, Kyrgyzstan, Osh Province, Batken region, Middle-Upper Triassic , Madygen Formation.

Diagnosis. Body densely covered with uniform circular tubercles. Antennae distinctly reaching behind base of pronotum; antennomeres 5–10 of subequal length, apical one longer than others. Base of antennae covered by supraantennal protuberance (Р1). Procoxae at pronotum mid-length. Main elytral veins differing only slightly from intercalary ones; no more than 24 cells in one row.

Description. Body to head length ratio 5.2–5.7. Cuticular tubercle size 0.02–0.03, space between adjacent tubercles 0.01–0.03; density of cuticular sculpture 380 tubercles per mm².

Head length definitely exceeds width, its basal 1/3 covered by pronotum. Eyes lie close to mandibular bases or distance between them not exceeding eye diameter; head length behind eyes 1.6–1.7× longer than eye diameter. Head not narrow posteriorly, only slightly so in front of eyes. Mandibles large, protruding forward, more or less straight, with only apices curved inwards, with three apical denticles with a vertical arrangement of teeth ( Fig. 1 , pink filling). Clypeolabrum protruding forward, have elongate-oval shape ( Figs 1B, D , 2F , cl-lab). Eyes large, slightly protruding laterally, with longitudinal diameter is 0.5, transverse diameter 0.2– 0.3, head width (excluding eyes) to eye diameter 4–4.3. Antennae filiform, attached immediately in front of eyes, antennomeres 3–6 are slightly widened anteriorly, others transverse, parallel-sided. Scapus enlarged, 1.5× as wide as long, 3× size of 2 nd antennomere, slightly longer than 3 rd, equal in size with 4 th, other antennal segments of equal size except that apical one slightly longer. Head with three pairs of protuberances (supraantennal protuberance, Р1; supraocular protuberance, Р2; posteromesal protuberance, Р3). Furrow visible in central part of the head dividing right and left protuberances; areas on sides of furrow forming ridges around eyes.

Pronotum transverse, almost not narrowing anteriorly. Pronotum 1.6× as wide as head; pronotal anterior margin not concave; anterior angles slightly protruding anteriorly. Posterior angles and posterior margin rounded; sides of pronotum straight. Dorsal aspect with pair of elongate-oval or bean-shaped medial elevations.

Prosternum. Notopleural suture straight, its apical third curved outward. Pleurosternal suture straight. Propleuron of equal width all along its length.

Elytral length to width ratio 3.4–3.8; elytron to pronotum width ratio 1.7. Humerus indistinct; basal 1/3 of epipleural margin straight; epipleuron to elytron width ratio at elytron mid-length 13–18. Main veins almost indistinguishable from intercalary ones. Veins 4 and 5 merge together before reaching elytral apex. Elytral cells large, rounded, occupying almost entire distance between the veins. Field I with full row of cells, cells in field II 23, field III 24, field IV 22–23, field V 18, field VI 18–21 in one row. Maculae present, cells near elytral base with 5–6 of them, cells at elytral mid-length with 7–8 maculae.

Mesoventrite slightly longer than mesocoxae.

Metaventrite as long as wide, anterior margin to posterior margin width ratio 1.9; longitudinal suture distinct, paracoxal suture approximate to but not merging with posterior margin of metaventrite.

Abdomen not narrowing forward, narrowing posteriorly at level of sternite III. Sternites I–IV with depression along their anterior margins. Sternites length ratio is 1.7–2:1:1:1:1.6–1.7. Procoxae adjacent, weakly transverse, large, making 1/3 of overall pronotal length; prosternal intercoxal process not fully separating procoxae ( Fig. 2B , in.cx.p). First two tarsomeres of fore legs of same length, other 3 shorter. First visible abdominal sternite to metacoxae length ratio 2–3.

Remarks. Similar to N. tenuis in head relief, procoxae shifted closer to pronotal mid-length and main veins almost indistinguishable from intercalary ones, but differs in bigger elytral cells and pronotum not narrowing in anterior half. Similar to N. tenuis and N. rostratus in antennal bases covered by supraantennal protuberance. Similar to N. tenuis , N. rostratus and N. oxypygus in having dense, uniform cuticular tubercles. In having large elytral cells similar to N. tuberculata ( Giebel, 1856) , N. foersteri Ponomarenko, 1968 , N. nigrimonticola Ponomarenko, 1968 and N. protensa Tan et al., 2006 , but differs in main veins almost indistinguishable from intercalary ones. It differs from N. tuberculate in narrower epipleuron and smaller size, from N. nigrimonticola in uniform cuticular tubercles, not serrated lateral margin of pronotum, narrower and straighter epipleuron with row of cells, rounded elytral cells and smaller size; from N. protensa in eyes close to mandibular bases, lateral margin of pronotum not serrated, epipleuron narrower and straighter, and last sternite more tapering and sharper and with more maculae.

Differs from the congeners in having antennae clearly reaching behind pronotal posterior margin and pronotum almost rectangular and not narrowing anteriorly. The long antenna is unusual for ommatids which usually have antennae shorter.

In having procoxae located closer to the center of pronotum instead of its posterior margin, make N. laticella similar to representatives of Tshekardocoleidae , Rhombocoleidae and Permocupedidae . However, elongated head, mandible three-toothed with a vertical arrangement of teeth, prothoracic intercoxal process incomplete and not reaching behind the coxae, double elytral cell rows with almost longitudinally-oriented veins and the veins 3 and 4 fused before reaching elytral apex suggest placement in Ommatidae . It seems that only this species of Notocupes has the procoxae lying closest to the procoxal center: Even N. tenuis has the procoxae slightly shifted to posterior margin.

The pronotal intercoxal process was originally mentioned in regard of material from China (e. g., N. alienus (Tan & Ren, 2006)) and South Korea ( N. premeris Lee et al., 2022 ). Among Notocupes from the PIN RAS collection, this is the only specimen that enables observation of this character. The aforementioned species were depicted with intercoxal process dividing the procoxae, but our observations suggest contiguous procoxae underneath a short, triangular process ( Fig. 2 А, B).

Figures

FIGURE 1. Notocupes laticella, holotype (PIN, 2555/1663). A, Photo of part. B, Interpretative line drawing of part. C, Mirrored photo of counterpart wetted with 95% ethanol. D, Interpretative line drawing of mirrored counterpart. Abbreviations here and elsewhere: an.p, antennal pit; cl-lab, clypeolabrum; el, elevation; P1, supraantennal protuberance; pr.cx, procoxae; pr.re, procoxal rests. Pink filling indicates mandibles; light grey—head; dark grey—profemur.

FIGURE 2. Notocupes laticella, paratypes (PIN, 2240/71, 74). A, Wetted with 95% ethanol PIN, 2240/74. B, Interpretative line drawing (square here and beyond shows relative size and density of tubercles). С, General scheme of elytra. D, Wetted with 95% ethanol PIN, 2240/71, counterpart. E, Interpretative line drawing. F, Interpretative line drawing of PIN, 2240/71, part. G, Photo of dry PIN, 2240/71, part. Abbreviations here and elsewhere: in.cx.p, intercoxal process; mesan, mesanepisternum; mesep, mesepimeron, mesotr, mesotrochantin; mesovent, mesoventrite; metanep, metanepimeron; metatr, metatrochantin; metavent, metaventrite; mnd, mandible; P2, supraocular protuberance; P3, posteromesal protuberance; s.n.pl, notopleural suture; s.pl.st, pleurosternal suture.

FIGURE 3. Notocupes laticella, paratypes. A–C, PIN, 2555/1662. Wetted with 95% ethanol (A), dry (B) and interpretative line drawing (C). D, Photo of dry PIN, 2555/1686. E–G, PIN, 2240/6. Wetted with 95% ethanol (E) and dry (F). G, Interpretative line drawing. Abbreviations: pr.tr, protrochantin; pr.tr-er, protrochanter; pr.tib, protibia.