Jurodes minor Ponomarenko, 1990

Yan, Evgeny V., Strelnikova, Olesya D. & Ponomarenko, Alexander G., 2021, Jurodidae (Coleoptera: Archostemata) from Transbaikalia: new findings and redescription of type material, Palaeoentomology 4 (6), pp. 604-613 : 607-609

Jurodes minor Ponomarenko, 1990

( Figs 4–5 )

Material. Holotype PIN, 3015/1254, part and counterpart of a body with antennae and most parts of the legs missing . Paratypes PIN, 3015/365, 372–374, 378, 1170, 1258–1260, 1262 from the type locality. From Daya locality specimens : PIN, 3063/115. Savino locality specimens : PIN, 1858/190, Upper Jurassic– Lower Cretaceous , Glushkovo Formation, Chita region .

Diagnosis. Alacrista on metanotum parallel-sided, undersides of elytra without transverse ridges.

Type locality and horizon. Unda locality, Lower Cretaceous , Glushkovo Formation, Russian Transbaikalia .

Description. Head not shorter than pronotum, as long as wide; heavily sculptured, with pair of oblique posteromesal protuberances (P3) converging anteriorly and posterolateral protuberances (P4) right behind them, shaped like a pair of transverse, oval bulges with a narrow bridge connecting them. Sides of head with longitudinal antennal grooves. Mandibles stout, almost triangular, as long as compound eye, ¼ of their length projecting beyond anterior labral margin; apical fourths curved inwards, outer margins straight; preapical teeth absent; mandibles reinforced by median ridges. Labrum rectangular, twice as long as clypeus, with rounded anterior angles; only slightly widening posteriorly. Clypeus strongly transverse, its visible part 4 times as wide as long, posterior margin straight. Frontal region between antennal insertions close to frontoclypeal suture; antennae attached closer to anterior frontal angles than to each other. Antennae filiform; length of antennomere exceeds width, somewhat increasing towards apices; apical antennomeres elongateoval; most flagellomeres apparently widening apically.

Pronotum not shorter than head, carinate, with pair of narrow longitudinal protuberances. Mesoscutellar shield semi-oval, anterior angles slightly protruding forward.

Elytra carinate, maximum width at distal third, with at least 14 punctate rows with no less than 36 punctures in one row. Hindwing costal margin thick, formed by three veins, C+ScA, ScP and RA; ScP most heavily sclerotized (judging from dark coloration); radial cell (rc) pentagonal, as long as triangular oblongum (o); sclerotized fold of membrane present near oblongum, facing wing apex.

Mesocoxae only separated at base by short and wide anteromedian process of metaventrite.

Metathorax with V-shaped alacrista; metascutum subdividedbydistinctlines,medianscutalimpressiondeep; metascutellum small, medially incised; metapostnotum with pair of median grooves. Anapleural cleft clearly visible, deep; longitudinal ridge of metaventrite (discrimen) clearly visibly, extending over entire length; paracoxal suture strongly shifted towards posterior margin of metaventrite. Metatrochantins very narrow, stripe-like. Metacoxae short, slightly oblique, without coxal plates, laterally reaching slightly beyond metanepisternum.

Abdomen with membranous area between tergites and sternites equal in width to tergal length; apical tergite VIII semi-oval. Aedeagus trilobate.

Measurements (in mm). Body length, 4.9, width, 1.6, elytral length, 2.2, elytral width, 0.5.

Remarks. In addition to the type series there are more recent findings of full-body imprints of J. ignoramus from Khasurty locality: PIN, 5026/956, 5340/476, 1235, 3718, 3721.

Labrum is filled with grey on the Fig. 5E for better visibility since it is overlapped by mandibles.

Figures

FIGURE 4. Jurodes minor Ponomarenko, 1990. A and B, Holotype part and counterpart PIN, 3015/1254, wetted with 96% ethanol. C and J, Paratype PIN, 3063/115 head and antennae and full body, wetted with 96% ethanol. D, F, H, Paratypes PIN, 3063/115, 3063/1770 parts and counterparts, hindwings wetted with 96% ethanol. Е, Paratype PIN, 3015/372 metathorax and abdomen, wetted with 96% ethanol. G and I, Material from Khasurty locality 5026/956 part and counterpart. K, Paratype PIN, 3015/365. L, Paratype PIN, 3063/1262, metaventrite. А and H are mirrored. Scale bars = 1 mm.

FIGURE 5. Jurodes minor Ponomarenko, 1990 interpretative line drawings. A and B, Holotype. C and D, Original line drawings of the holotype from Ponomarenko, 1990 with minor changes. E, Details of paratype’s PIN, 3063/115 head. F–H, Paratypes PIN, 3063/115, 3063/1770 parts and counterparts, hindwings. I, Details of paratype’s PIN, 3015/372 metathorax and abdomen. J, Paratype PIN, 3063/115. K, Paratype PIN, 3063/1262, metaventrite. L, Paratype PIN, 3015/365. Abbreviations: 11, apical antennomere; AA, anal vein; aed, aedeagus; alc, alacrista; an.cl, anapleural cleft; ant, antennae; ant.g, antennal groove; apm, apical membrane; C+ScA, costa fused with subcosta anterior; clp, clypeus; CuA, cubitus anterior; CuA2, cubitus anterior, second branch; cx3, metacoxae; em3, metepimeron; es3, metanepisternum; lbr, labrum; md.p, median protuberance; mpn3, metapostnotum; msi, median scutal impression; o, oblongum cell; P3, posteromesal protuberance; P4, posterolateral protuberance; po.e, postocular extension; RA, radius anterior; rc, radial cell; sc2, 3, meso- and metascutum; scl2, mesoscutellum; ScP, subcostal posterior; s.prc, paracoxal sutures; s.scl3, metathoracic scutoscutellar suture; TI-VIII, abdominal tergites; tb2, mesotibia; tr3, metatrochantin; trh3, metatrochanter. Figures G and H are given with the single scale bar. Scale bars = 1 mm.