Anthracoptilidae Handlirsch, 1922

Guan, Zhaoying, Prokop, Jakub, Roques, Patrick, Lapeyrie, Jean & Nel, André, 2016, Revision of the enigmatic insect family Anthracoptilidae enlightens the evolution of Palaeozoic stem-dictyopterans, Acta Palaeontologica Polonica 61 (1), pp. 71-87 : 72-73

Family Anthracoptilidae Handlirsch, 1922

2002 Strephocladidae Martynov, 1938 ; Rasnitsyn 2002: 112.

2002 Strephoneuridae Martynov, 1940 ; Rasnitsyn 2002: 112, 114.

Type genus: Anthracoptilus Lameere, 1917 for Anthracoptilus perrieri Meunier, 1909 ); Stephanian, Carboniferous (= Gzhelian, Upper Pennsylvanian), Commentry Basin, Allier department, France.

Emended diagnosis.—Area between C and ScP with a series of veinlets and crossveins (but probably not preserved in Strephocladus permianus ); RA with one or two posterior branches (an apomorphic character, but not shared by all taxa in Anthracoptilidae ) or simple; median vein strongly approximate or shortly fused with RP near base of RP (synapomorphy); branches of RP, median vein and CuA strongly parallel at least in their basal halves(the presence of branches all simple is not shared by all taxa in Anthracoptilidae ); median vein braced to CuA by a short convex cross-vein mp-cua (a character present in Holometabola, Paoliida and Dictyoptera, but very useful to separate the Anthracoptilidae from the archaeorthopteran taxa); CuA and CuP emerging from a long common stem; main stem of CuA strongly convex, but anteriorly pectinate with at least a series of parallel branches, all less convex than main stem of CuA (synapomorphy).

Remarks.—The family Strephocladidae Martynov, 1938 (type genus Strephocladus Scudder, 1885 ) is currently considered as a junior synonym of the family Anthracoptilidae Handlirsch, 1922 , also synonymized with the Permarrhaphidae Martynov, 1931 (late Permian, monotypic genus Permarrhaphus Martynov, 1931 ) and the Strephoneuridae Martynov, 1940 (early Permian, monotypic genus Strephoneura Martynov, 1940 ) (Rasnitsyn 2002; Novokshonov and Aristov 2004; Rasnitsyn and Aristov 2004; Rasnitsyn et al. 2004). Lastly Rasnitsyn and Aristov (2013) proposed again a synonymy of the Permarrhaphidae with the Anthracoptilidae , Strephoneuridae , Strephocladidae , but also with the Ischnoneuridae Handlirsch, 1906 and the Adiphlebiidae Handlirsch, 1906 (see below).

Comparisonoftypegenera Strephoneura , Strephocladus , Permarrhaphus , and Anthracoptilus leads to the following conclusions. Strephoneura shares with Strephocladus the following potential apomorphies: ScP and radius strongly approximate; RA with two apical posterior branches; RP and median vein strongly approximate or touching near base of RP; CuA with several pectinate anterior branches; branches of RP, median vein, and CuA all simple and closely parallel; CuP and first anal vein simple. Permarrhaphus venosus Martynov, 1931 is based on a wing fragment that was originally interpreted as a beetle elytron. It cannot correspond to any part of a strephocladid wing, except, maybe the anal area, as supposed by Rasnitsyn and Aristov (2004: 160). Nothing looking like a radius, median or CuA vein can be seen on the original photograph ( Martynov 1931: fig. 28). It remains that nothing supports the attribution of this wing to the same clade with Strephoneura or Strephocladus . Therefore, we remove the first synonymy of the Strephoneuridae with the Permarrhaphidae proposed by Rasnitsyn (2002: 112–114), but we confirm the synonymies of the Strephoneuridae and Strephocladidae with the Anthracoptilidae . We consider the Permarrhaphidae (and Permarrhaphus ) as Insecta incertae sedis status novus.

Anthracoptilus perrieri ( Meunier, 1909) (Gzhelian of Commentry, see redescription below), type species of the Anthracoptilidae , shares with Strephoneura and Strephocladus : the CuA and CuP emerging from a common stem; a distinct brace between CuA and median vein; median vein and RP approximating near base of RP; an anteriorly pectinate CuA with branches less convex than main stem of CuA; ScP ending on RA; branches of main veins parallel between them but less clearly than in Strephoneura and Strephocladus . Anthracoptilus differs from them in the presence of several branches of RP, median vein and CuA forked distally; presence of a net of very irregular sigmoidal crossveins, instead of being straight and defining rectangular cells between main veins; RA ending on anterior wing margin in a distinctly more basal position; RA without any posterior branches in its apical part (difference with Strephocladus , character unknown in Strephoneura ).

An anteriorly pectinate CuA is convergently present in the Archaeorthoptera of the subclade Cnemidolestodea Handlirsch, 1937 (sensu Béthoux 2005a), but the patterns of venation of these orthopteroid insects are completely different from those of the Anthracoptilidae , due to presence of basal fusion of CuA with M in the former and to a common stem Cu from which CuA and CuP emerge in the latter. Furthermore, the anterior branches of CuA (+CuPa) are clearly concave in the Cnemidolestodea , while the same branches are relatively more convex in the Anthracoptilidae . Rasnitsyn and Aristov (2013), refusing the argument of convexity of the different veins, proposed to synonymize the Anthracoptilidae with the Ischnoneuridae (type genus Ischnoneura Brongniart, 1893 (Gzhelian of Commentry), without giving any argument against the attribution of Ischnoneura to the archaeorthopteran lineage (and more precisely to the Cnemidolestodea ; see Béthoux 2005a), as proposed by Béthoux and Nel (2005: fig. 19), on the basis of the pattern of forewing venation typical of those of the Archaeorthoptera, especially in the presence of a concave anterior branch of CuP reaching the convex CuA, itself emerging from a common stem with M. We reject this synonymy and restore the Anthracoptilidae as a separate family, in a different clade that does not belong to the Archaeorthoptera, unlike the Ischnoneuridae . More recently, Aristov (2014) synonymized the Ischnoneuridae (at least its type genus Ischnoneura ) with the Cnemidolestidae Handlirsch, 1906 , type family of the Cnemidolestodea , but without speaking again his previous proposal of synonymy of the Anthracoptilidae with the Ischnoneuridae .

Note that some holometabolous Permochoristidae ( Protopanorpa spp. ) also have a similar pattern of a curved vein in mid part of wing with a series of anteriorly pectinate and parallel branches, separating basally from a simple vein, but the concerned veins are completely different, the anteriorly pectinate vein being MP while the simple posterior vein is CuA (see Bashkuev 2010: fig. 1). Also the Plecoptera penturoperlid Penturoperla have a median vein with a series of parallel anterior branches ( Illies 1960), even in some of them could be in fact interpreted as branches of CuA captured by median vein following Béthoux (2005b). These similarities support the hypothesis of a convergent evolution between the Archaeorthoptera Cnemidolestodea and the Paoliida Anthracoptilidae , due to flight ability.

Stratigraphic and geographic range.—Bashkirian (Lower Pennsylvanian)–Lopingian (upper Permian), Australia, Europe, North America, and Russia.