Plesioschwinzia Zessin, 1988

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 : 201-202

Genus Plesioschwinzia Zessin, 1988

Type species. Plesioschwinzia thalassophila Zessin, 1988

Remarks. The genus was described from one aberrant tegmen having four more or less long and oblique branches of Sc, a primitive structure of MA (with 1MA1, 2MA1 and MA2 located as in Locustopsis and Mesolocustopsis ), two branches of MP+CuA1 (as in Locustopsis and Zeunerella ), and unusual venation in the area between MA and MP+CuA1. The latter area has a false branch arising from MA before the MA2 base and additionally connecting MA with the costal branch of MP+CuA1 (this is undoubtedly an individual aberration of venation, sometimes occurring in one or even both tegmina of some specimens of recent Orthoptera species). Thus, the presence of such a branch cannot be a generic or species diagnostic character. Differences of this genus from Locustopsis are mainly in the less numerous long oblique branches of tegminal Sc (1–4 instead 6–8); this character is not reliable, because intermediate variants are possible, and many specimens have an inadequately preserved costal area. This genus differs from Schwinzia in the presence of two (instead of three) branches of tegminal MP+CuA1 (possibly the Early Jurassic species Locustopsis anatolica Sharov, 1968 , also having three branches of tegminal MP+CuA1, could be tentatively included in the genus Schwinzia ). Plesioschwinzia is distinguished from Parapleurites by its distinctly longer Sc, if the tegmen of its type species P. gracilis Brauer, Redtenbacher & Ganglbauer, 1889 was correctly pictured by the authors ( Brauer et al., 1889: fig. II, 17).

This genus may contain several species originally placed in other genera, which had a long Sc with 1–4 rather long and oblique branches in its proximal and middle parts, a primitive MA and two branches of MP+CuA 1 in the tegmina: Gomphocerites bernstorffi Geinitz, 1880 , Locustopsis lacera Zessin, 1983 , L. procera Zessin, 1983 , L. pulchella Zessin, 1983 , and L. kruegeri Zessin, 1983 from the Lower Jurassic of Germany; L. lacoei Cockerell, 1916 , L. uvarovi Zeuner, 1942 , L. gracilis Zeuner, 1942 , and L. constricta Zeuner, 1942 from the Lower Jurassic of England; L. posterior Gorochov, Jarzembowski & Coram, 2006 from the Lower Cretaceous of England. However, the last two species, as well as some of the others, may have been based on specimens in which only some of an originally greater number of Sc branches were visible, and so may not belong to Plesioschwinzia . However, the type species of this genus and the new species, described below, undoubtedly have only four such branches.