Beaconiella cincta Shcherbakov, 2021

Shcherbakov, D. E., 2021, New Curvicubitidae and Paraknightiidae (Homoptera: Cicadomorpha) from the Triassic of Central Asia, Russian Entomological Journal 30 (2), pp. 129-134 : 132

Beaconiella cincta Shcherbakov , sp.n.

Figs 5–8 .

MATERIAL. Holotype tegmen PIN 2785 / 3107(3381)±. Paratypes: tegmina PIN 2555 / 2192(2866)±, 3514(3642)±; hindwing PIN 2240 / 2931; Dzhailoucho (Madygen, northern area), Leilek District , Batken Region, SW Kyrgyzstan; Madygen Formation, Ladinian–Carnian .

DESCRIPTION. Tegmen ~ 22–26 mm long, 9.9–11 mm wide (~22 x 9.9 mm in holotype), variation exaggerated by rock distortion; √LW 14.8–16.7 mm (x1.13). Tegmen fuscous with large pale streaks along anterior margin and two incomplete oblique pale bands — just before nodal line and from nodus towards tornus. Interradial area about as wide as radial area. MA fork and usually RP fork distant from nodal line. RP, M and CuA altogether with 45–50 terminations. Branches of MP and CuA sometimes not forming one bunch. Hindwing 23.1 mm long, 10.0 mm wide; RA, RP and M forked about same level, CuA more distally .

COMPARISON. Very similar to B. pulchra , but larger, with more prolific venation and well developed pale bands. Differences from the Australian species are the same as in B. pulchra . Distinct from B. triassica in the richer and denser distal venation and sigmoidal CuA branches in the tegmen: in the latter species, RP, M and CuA altogether have about 30 terminations, and CuA branches converge with the posterior wing margin.

REMARKS. The difference in size between B. cincta and B. pulchra seems too great to be explained only by sexual dimorphism in size within the same species. For example, in the modern archaic cicadoid Tettigarcta tomentosa White, 1845 the tegmen length in the largest females is only x1.28 greater than in the smallest males [ Moulds, 1990]. Secular fluctuations in average size within one species also seem unlikely, because both the largest B. cincta tegmen and the smallest B. pulchra tegmen were collected by the same field party in 1965, presumably from the same layer.

ETYMOLOGY. Latin cinctus (girded).

Superfamily Scytinopteroidea Handlirsch, 1906

Family Paraknightiidae Evans, 1950

DIAGNOSIS. Rather small, dorsoventrally depressed hoppers with well-developed pronotal paranota. Tegmina heavily sclerotized, punctate, folded nearly flat in repose and at least slightly overlapping distally. Tegmen: Basal cell very long, tapered near apex, closed with long basal section of M and short arculus; subcostal arc reduced. RA either very long, longitudinal, with dSc separating far from its base, or subtransverse and parallel to dSc and RP branches; dSc weakly convex. More than one r-m crossvein. Transverse groove at nodal level rudimentary or absent, M straight there and connected with CuA (or CuA1) by crossvein. Clavus with convex stripe along commissural margin. Survace densely punctate, sometimes except smooth posterodistal part.

COMPOSITION. Paraknightia Evans, 1943 , Tychticola Becker-Migdisova, 1952 , Triknightia gen.n.

Figures

Figs 1–8. Beaconiella spp., Madygen, Triassic: 1–4 — B. pulchra sp.n.: 1–2 — holotype tegmen; 3–4 — paratype hindwing PIN 2555/ 2320 (images mirrored): 3 — hindwing; 4 — coupling hooks along costal margin, SEM; 5–8 — B. cincta sp.n., holotype tegmen:5 — tegmen; 6–8 — SEM: 6 — proximal part of tegmen; 7 — nodus (note granules on veins); 8 — CuA branches (note marginal membrane). Scale bars: 1, 3, 5 — 5 mm, 2 — 3 mm, 4 — 0.5 mm, 6 — 2 mm, 7–8 — 1 mm. Рис. 1–8. Beaconiella spp., Мадыген, триас: 1–4 — B. pulchra sp.n.: 1–2 — переднее крыло, голотип; 3–4 — Заднее крыло, паратип ПИН 2555/2320 (перевернуто Зеркально): 3 — Заднее крыло; 4 — сцепочные крючки по костальному краю, СЭМ; 5–8 — B. cincta sp.n., переднее крыло, голотип: 5 — переднее крыло; 6–8 — СЭМ: 6 —проксимальнаЯ часть крыла; 7 — нодус (видны Зёрна на жилках); 8 — ветви CuA (видна периферическаЯ мембрана). Длина масШтабных линеек: 1, 3, 5 — 5 мм, 2 — 3 мм, 4 — 0.5 мм, 6 — 2 мм, 7–8 — 1 мм.