Parapalaeomastax dariuszi, Dvořák & Pecharová & Krzemiński & Prokop, 2019

Dvořák, Tomáš, Pecharová, Martina, Krzemiński, Wiesław & Prokop, Jakub, 2019, New archaeorthopteran insects from the Carboniferous of Poland: Insights into tangled taxonomy, Acta Palaeontologica Polonica 64 (4), pp. 787-796 : 793-794

Parapalaeomastax dariuszi sp. nov.

Fig. 4 .

ZooBank LCID: urn:lsid:zoobank.org:pub:08E34AA1-C66D-4FAF-A4C1-49F61D87A63B

Etymology: In honour of our colleague and collector of Carboniferous fossils Dariusz Wojciechowski.

Holotype: MP ISEA I− F/ MP/ 1540 /20/09 (imprint of forewing).

Type locality: Sosnowiec-Klimontów, originally Porąbka-Klimontów Mine, Upper Silesian Coal Basin, Poland ( Krawczyński et al. 1997, 2001).

Type horizon: Pensylvannian, Langsettian (Westphalian A), Coal-bearing Mudstone Series, Mudstone series (Załęże beds) (Pacyna and Zdebska 2012).

Diagnosis. —Vein M distally divided into MA and MP, MA shortly braced to RP. Free part of M before bifurcation four times or less longer than width of costal field where CuA+M divides.

Measurements.—Forewing fragment length 34.4 mm long, estimated forewing length 55 mm, maximum width in widest preserved part 14 mm (estimated maximum width is probably only slightly larger).

Description. —Based on fore-wing venation. Wing generally incompletely preserved, cubital area partly distorted, apex missing. Wing membrane hyaline, numerous transverse or slightly oblique crossveins regularly arranged. ScA unknown, ScP ends on costal margin in distal third of wing. Costal area broad with regular pattern of numerous oblique veinlets. R almost straight, bifurcated 6.18 mm distal from divergence of M and CuA. RA probably simple. RP posteriorly pectinate, ending with at least three terminal branches. Short stout brace present between RP and MA. Long basal fusion between M+CuA. M diverging from the common stem well before the middle of the wing. M divided into MA and MP beyond the middle of the wing. Short brace between MA and RP 2.3 mm from M bifurcation. MA and MP run parallel to one another over a long distance. Distal bifurcation of both M veins present close to posterior margin of wing. CuA fused with CuPa shortly after its emergence from the M+CuA vein. CuPb probably simple. Details of cubital area indistinct, but posterior pectination of CuA+CuPa ending with at least 4 primary branches, the first of which is secondarily bifurcated. Anal area formed by at least two anal veins, second anal vein distally bifurcated.

Remarks. —This forewing corresponds to that of Archaeorthoptera sensu Béthoux and Nel, 2002 because of the following synapomorphies: CuP differentiated into two branches (CuPa and CuPb), M and CuA fused over long distance and distal part of CuA fused with CuPa. Despite a poorly preserved cubital area, there is no sign of a branched CuPa vein, so it is unlikely that it can be placed in Panorthoptera . Wide space between RA and RP lead us to exclude this fossil from Lobeattida. Due to posteriorly pectinate CuA+CuPa vein, we can also exclude the placement within Cnemidolestodea

CuA+CuPa

Béthoux 2005). AP area is indistinct, but is probably not well developed, and therefore our fossil cannot be placed in Protophasmida. Nevertheless, the general pattern of the venation of this fossil resembles that of the group of genera consisting of Coselia , Omaliella , Paralongzhua , Omalia , and especially Palaeomastax ( Béthoux and Nel 2005; Prokop et al. 2015).

Parapalaeomastax gen. nov. differs from Omalia with Omalia macroptera , especially by its more distal division of MA and MP and connection of MA by only a short brace to RP, instead of a partial fusion ( Béthoux and Nel 2005). There is also a more complicated pattern of cross veins in the costal area in O. macroptera and the same is true for Omalia sp. (specimen MGL 4217), where in addition, the bifurcation of MP is closer to the division of MA and MP ( Béthoux and Nel 2005). Coselia mainly differs from Parapalaeomastax in having a markedly wider costal area with a prominent meshwork of cross veins, but the type species of C. palmiformis is based only on the basal part of a wing. In Omaliella with Omaliella ramosa the branching pattern of M is different and vein RP is connected to the anterior branch MA1. The comparison of Parapalaeomastax with early Permian Paralongzhua based on Paralongzhua elongata from Lodève (Hérault, France) reveals it has a much narrower costal area, the division of MA and MP located more basally and MA is deeply bifurcated ( Prokop et al. 2015). Palaeomastax Handlirsch, 1904 based on Palaeomastax carbonis from Frameries in Belgium has the same general pattern of venation, with the exception of a long and simple M unlike our fossil with deeply branched M and MA shortly braced to R ( Béthoux and Nel 2005). But the fossil of P. carbonis lacks distal part of wing and even the distal end of the preserved part is damaged. It is quite plausible, that a bifurcation of M and a connection of MA with RP can occur immediately distal to the preserved area. However, we have to stick to the facts. So, the long simple M is a crucial diagnostic character of the genus Palaeomastax and therefore provides sufficient differentiation of Parapalaeomastax , but we need to search for more complete fossils of Palaeomastax in order to accurately compare their wing apices.

Stratigraphic and geographic range.—S Poland: Upper Silesia, Sosnowiec-Klimontów; Pensylvannian, Langsettian (Westphalian A).

Figures

Fig. 4. Forewing venation of archaeorthopteran insect Parapalaeomastax dariuszi gen. et sp. nov., holotype (MP ISEA ISEA I−F/MP/1540/20/09), Carboniferous, Pensylvannian, Langsettian (Westphalian A), Sosnowiec-Klimontów, Upper Silesian Coal Basin, Poland. Photograph (A1) and explanatory drawing (A2). Abbreviations: A1, first anal vein; CuA, cubital anterior; CuPa/b, anterior/posterior branch of cubital posterior; MA/P, media anterior/ posterior; RA/P, radius anterior/posterior; ScP, subcosta posterior.