Syntonopteridae, Handlirsch, 1911

Tenny, Jakub Prokop André Nel Andrew, 2010, On the phylogenetic position of the palaeopteran Syntonopteroidea (Insecta: Ephemeroptera), with a new species from the Upper Carboniferous of England, Organisms Diversity & Evolution (New York, N. Y.) 10 (4), pp. 331-340 : 337

Syntonopteridae and some potentially related smaller taxa: the Syntonopteroidea

Some palaeopteran taxa could be more closely related to Syntonopteridae than to any other clade. These are:

(1) Miracopteron Novokshonov, 1993 (the sole genus of Miracopteridae Novokshonov, 1993 ). This is an enigmatic Lower Permian taxon based on isolated wings (see Novokshonov 1993; and Fig. 6 ). The Miracopteridae share with the Syntonopteridae the presence of a characteristic constriction of the area between AA1+2 and AA3+4, the presence of a concave longitudinal vein between them (vein IN-), and a constriction of the area between AA3+4 and the first branch of the concave AP at the same point, plus very similar overall wing venation patterns (see Fig. 6 ). Rasnitsyn (2002: 89) suggested that Miracopteron could belong to the ‘Syntonopterida’, and be closely related to the Syntonopteridae , without giving a precise argument. The main difference between Miracopteron and Syntonopteridae is the presence of posterior branches of CuP in the former.

(2) Bojophlebia Kukalová-Peck, 1985 ( Bojophlebiidae Kukalová-Peck, 1985 ). Following Kukalová-Peck’ s (1985) interpretation, the wing in this taxon would lack the above-mentioned peculiarities of the anal area, and have a distinct convex costal brace, unlike that of Lithoneura . However, Kukalová-Peck’ s (1985) interpretation is far from convincing, as the holotype specimen of Bojophlebia is very poorly preserved ( Fig. 7 ). In fact, it is impossible to see whether there is a ScA, and the basal part of the anal area is hardly preserved.

Thus we newly propose here to exclude Bojophlebiidae from the Syntonopteroidea , considering it as Pterygota incertae sedis instead, and to characterize Syntonopteroidea by the presence of the specialized structures of the hind wing anal area listed above. We also propose to include Miracopteron and the Miracopteridae within the Syntonopteroidea .

Putting Miracopteridae and Syntonopteridae into a superfamily or order is an arbitrary choice at this stage, because their relationships with Ephemeroptera and Odonatoptera remain rather uncertain (see below). Rasnitsyn (2002) proposed to maintain order rank for the “considerable phenetic distance from the true mayflies as well as their probable paraphyletic (ancestral) position in respect to both mayflies and dragonflies.” Such arguments to create or maintain orders are not well-grounded, because ‘phenetic distance’ is a subjective concept. Moreover, we follow the rule that sister-taxa should be of the same rank.

Figures

Fig. 6 Miracopteron mirabile Novokshonov, 1993, holotype (No. 2/ 135, Paleontological Institute, Russian Academy of Sciences, Moscow); photograph of counterpart. Scale bar 10 mm

Fig. 7 Bojophlebia prokopi Kukalová-Peck, 1985, holotype (No. 1/ 1985, National Museum Prague, Czech Republic); photograph of counterpart. Scale bar 50 mm