Piesbergopterum avionensis, NEL & ROQUES, 2021

NEL, ANDRÉ & ROQUES, PATRICK, 2021, The second species of the cnemidolestid genus Piesbergopterum from the Upper Carboniferous of Avion, Northern France (Archaeorthoptera: Cnemidolestidae), Palaeoentomology 4 (4), pp. 323-325 : 323

Piesbergopterum avionensis sp. nov.

( Figs 1 , 2 )

Material. Holotype MNHN.F.A71354 (imprint and counterimprint of a nearly complete forewing, with only apical part of radial area missing), stored at the Muséum National d’Histoire Naturelle , Paris, France.

Etymology. Named after the locality of Avion.

Diagnosis. Forewing with anterior branch of MP+CuA+CuPa with three posterior branches; posterior branch of MP+CuA+CuPa with only two anterior branches; division of RA and RP close to connection of ScP on RA.

Locality and horizon. ‘Terril N°7’, Avion, Pas-de- Calais, France; Moscovian (Westphalian C/D equivalent to Bolsovian/Asturian).

Description. Based on forewing venation. Length of preserved part 17.2 mm; estimated total wing length ca. 20 mm, maximum width at midwing 7.1 mm; prominent bending of costal margin in about basal third; wing membrane probably originally darkly coloured with a pattern of hyaline spots inside cells separated by crossveins; concave ScP slightly curved, running parallel with costal margin, ending to RA behind midwing; costal area broader than subcostal area with numerous simple and oblique crossveins; stem of R diverging from M+CuA near base of wing; division of RA and RP proximal of midwing, 2.1 mm basal to connection of ScP on RA; strongly convex RA simple; oblique crossveins present in space between RA and costal wing margin; concave RP posteriorly pectinate ending with at least four (probably five or six originally) simple branches covering whole distal part of wing; vein MA diverging from M+CuA and further running parallel to stem of R/RP; MA with a posterior branch and an anterior branch shortly connected with RP; concave vein CuPa ending into MP+CuA shortly behind divergence of MA from MP+CuA; MP+CuA+CuPa emitting a posterior branch subdivided into two anterior branches; and an anterior branch parallel to MA, emitting three simple posterior branches, and distally ending into MA, thus defining a large area between it and MA crossed by irregular veinlets; area between branches of RP, MA and MP+CuA+CuPa regularly connected by simple and oblique crossveins; concave CuP basally dividing into CuPa and CuPb, CuPb running parallel to MP+CuA+CuPa towards posterior wing margin; convex PCu running parallel to CuP and CuPb; anal vein distally connected to PCu.

Figures

FIGURE 1. Piesbergopterum avionensis sp. nov., holotype MNHN.F.A71354. Photographs. A, Imprint. B, Counterimprint, black arrowhead base of RP; yellow arrowhead apex of ScP; white arrowhead base of first branch of MP+CuA+CuPa; red arrowheads bases of posterior branches of first branch of MP+CuA+CuPa. Scale bars = 3 mm.

FIGURE 2. Piesbergopterum avionensis sp. nov., holotype MNHN.F.A71354. Photograph. Imprint. Scale bar = 3 mm.