Plesioschwinzia sharovi Gorochov & Coram, 2023

GOROCHOV, ANDREI V. & CORAM, ROBERT A., 2023, New and little known taxa of the order Orthoptera (Insecta) from the Upper Triassic and Lower Jurassic of England, Palaeoentomology 6 (2), pp. 198-204 : 202-203

Plesioschwinzia sharovi Gorochov & Coram sp. nov.

( Fig. 2 )

Type material. Holotype, imprint RS/Orth 1 ( ZIN), counterpart ( Fig. 2B ); tegmen without proximal part; collected by R. Coram.

Etymology. Dedicated to the memory of the famous Russian palaeoentomologist-orthopterologist A.G. Sharov.

Diagnosis. The tegmen of the new species differs from the majority of true and possible congeners in that the base of MA2 is located distinctly less close to the MA1 bifurcation. In addition, it is distinguished by the following tegminal characters: from P. thalassophila and P.? pulchella also having four long and oblique branches of Sc, by longer branches of MP+CuA1 and a shorter distance between CuA2 base and MP+CuA1 bifurcation (from P. thalassophila only), or by a clearly longer RS with its base located distinctly closer to the apex of the precostal area (from P.? pulchella which has this base located behind all the visible branches of Sc); from P. bernstorffi , P. kruegeri , P. uvarovi , P. gracilis , P. lacera , P. lacoei and P. procera , by more numerous (not two or three) Sc branches. The new species differs from P.? constricta and P.? posterior in the presence of four (rather than one) long and oblique tegminal Sc branches; additionally, it differs from the first species in that the base of tegminal MA2 is located much closer to the MA1 bifurcation, and from the second species, in having a tegmen with a clearly narrower CuA-CuP area and the MP+CuA1 branches being not fused with each other by their distal parts.

Type locality and horizon. Upper Triassic , Rhaetian, Penarth Group, Lilstock Formation, Cotham Member, Blue Anchor Point, Somerset, UK (national UK Grid Reference ST 033 435) .

Description. Male tegmen ( Fig. 2A ): precostal area with numerous and dense oblique branches in distal portion; costal area long (apex of Sc located far behind bases of all branches of RS), with four more or less long and oblique branches of Sc as well as a very narrow distal half; RS with four branches and with base located not far from apex of precostal area; base of MA2 located some distance from MA1 bifurcation; area between MA and MP+CuA1 moderately wide, significantly wider than R-M area but insignificantly wider than CuA-CuP area, with crossveins somewhat irregular, MP+CuA1 with two branches practically parallel to MA branches, but anal branch of MP+CuA slightly arcuate and with apex located very near apex of costal branch of this vein; distance between base of CuA1 and MP+CuA1 bifurcation not long; area CuA-CuP without any distinct widening near base of CuA2. Length of imprint 12.3 mm; possible length of tegmen 15 mm.

Figures

FIGURE 2. Plesioschwinzia sharovi sp. nov., tegmen, holotype RS/Orth 1, Somerset, Upper Triassic. A, Reconstruction of venation. B, Photograph of imprint (counterpart). Scale bar = 3 mm.