Archaeochrysa sp.

Makarkin, Vladimir N., Antell, Gwen S. & Archibald, S. Bruce, 2022, A revision of Chrysopidae (Neuroptera) from the late Eocene Florissant Formation Colorado, with description of new species, Zootaxa 5133 (3), pp. 301-345 : 308-309

Archaeochrysa sp.

Figs 5 , 6

Palaeochrysa sp. : Meyer 2003: Fig. 163.

Type material. Specimen NHM.I.26921, deposited in the NHM. A nearly complete specimen in ventral aspect.

Type locality and horizon. USA: Colorado: Teller County: Florissant (precise collecting locality unknown); Eocene , late Priabonian ; Florissant Formation .

Description. Body ca. 10.7 mm long, poorly preserved. Antennae, legs not preserved.

Forewing ca. 13.3 mm long, ca. 4.8 mm wide (length to width ratio ca. 2.77). Costal margin slightly convex. Costal space relatively broad. Subcostal veinlets simple proximad pterostigmal region, rather widely spaced. Pterostigma distinct, long, fuscous; incorporated veinlets not discernible. Sc long (its distal part Sc poorly discernible). Subcostal space narrow; subcostal crossveins not discernible. RA ending on margin just before apex; three to four distal veinlets preserved distad pterostigma. RA space broad, with 18 rather closely spaced complete crossveins and one incomplete (right wing). RP originating relatively close to wing base (at 0.19 of complete length). Anterior trace of RP zigzagged, apically not forked; with 10 forked branches (RP9, probably RP1 simple). Basal crossvein between RP, M (1r-m) relative long, connecting anterior trace of RP, MA at proximal end of im. M dividing to MA, MP far distad origin of RP. MA, MP, im strongly crumpled. Psm poorly developed, zigzagged. CuA, CuP only proximally discernible. 1icu located far from origin of CuP; c1: c2 length ratio 0.82:1. A1 deeply forked. A2 probably simple. Two gradate series of crossveins nearly parallel; inner series with 10 crossveins distad MA; outer series with eight crossveins distad RP2.

Hind wing ca. 11.5 mm long, ca. 4.0 mm wide. Costal space narrow. Preserved subcostal veinlets simple proximad pterostigmal region, rather widely spaced. Pterostigma distinct, long, fuscous; incorporated veinlets not discernible. Sc long, its distal part poorly discernible. Subcostal space very narrow; subcostal crossveins not discernible. RA long (its apex not preserved). RA space broad, with 15 rather closely spaced crossveins. RP originating close to wing base (at ca. 0.11 of complete length). Anterior trace of RP slightly zigzagged, with eight pectinate branches; probably all forked. Basal crossvein between RP, M (1r-m) present (incompletely preserved). Psm poorly developed, zigzagged. M not preserved. Proximal part of CuA, one branch of CuA, CuP, A1 all partially preserved. CuP basally perpendicular to A1, then these are probably fused for long distance; CuP simple. 1icu located far from origin of CuP, connecting CuA, anterior branch of CuP. Two gradate series of crossveins: inner series with eight crossveins distad MA; outer series with seven crossveins distad RP2.

Remarks. The preserved venation of the specimen is most similar to that of Archaeochrysa . Poor preservation of some critical areas of the wings (especially, shape of the intramedian cell) makes it difficult to assign the specimen to any known species or consider it a new species. Its crossvein 2icu is located distinctly proximad 1r-m, as in A. paranervis (in other Florissant species, this crossvein is only slightly proximad 1r-m), but the slight convexity of the costal margin and the forked A1 are more like A. fracta . However, the right forewing does not possess a crossvein between RA and RP proximad 1r-m, which all other specimens of Florissant Archaeochrysa have. The absence of this crossvein occurs, however, in some specimens of the type species from Creede.

Figures

FIGURE 5. Archaeochrysa sp., specimen NHM.I.26921 (counterpart). NHMUK PI I.26921 image © The Trustees of the Natural History Museum. Scale bar = 3 mm.

FIGURE 6. Wing venation drawings of Archaeochrysa sp., specimen NHM.I.26921. A, right forewing; B, right hind wing; C, left forewing. Veins that cannot be assigned to the right fore- or hind wings are shown by dotted lines. Scale bars = 3 mm (all to scale).