Kulbastavia grandis Kopylov, 2018

Kopylov, Dmitry S., 2018, Forgotten giants: new Anaxyelidae (Hymenoptera) from the Jurassic of Karatau, Zootaxa 4514 (3), pp. 332-340 : 335-336

Kulbastavia grandis Kopylov , sp. nov.

( Fig. 3 , 4C )

Etymology. The name is the Latin adjective ‘grandis’ (large) due to the size of the species.

Material. Holotype: PIN, no. 2997/5000, from Karatau ( Kazakhstan), part without counterpart, imago, female. Good preservation of fore wings, though the hind wings are partially preserved; the sculpture of thorax is not preserved, the fore segments of the abdomen are indistinguishable; the legs, basal antennomeres, and the apex of the ovipositor are not preserved.

Description. Wing veins uniformly dark, membrane not coloured; body light, excluding two last darker segments of abdomen (possibly this colouration is a consequence of the poor preservation); eyes very dark; middle antennomeres dark, apical (and, probably, basal) light, ovipositor dark. Eyes elongated-oval, eye height equals 0.4 of head height. Antenna flagellum with no less (and probably not much more) than eight flagellomeres (basal parts of antennae not preserved), flagellomeres slightly swollen, gradually shorten and become thinner apically; ratio of length to width in flagellomeres gradually decreasing apically from 3.2 (the first preserved flagellomere)–2.3 (subapical one); apical flagellomere rounded at the top, 1.1 × as long as and as wide as subapical one; two apical flagellomeres are light, whereas basal flagellomeres are dark-coloured. Two teeth are distinguishable on the mandible; however, it is quite possible that not all the teeth are preserved. Fore wing with costal cell narrow, its width does not exceed the thickness of vein C; Sc transverse, slightly proclined, located closely to base of 1-Rs; pterostigma completely sclerotized, 5.0 × as long as wide; 1-Rs 3.3 × as long as 1-M and 2.0 × as long as Rs+M; 1r-rs and 2r-rs strongly oblique; 1r-rs 2.2 × as long as 2-Rs; 3-R slightly curved backwards, 2.2 × as long as 1r-rs; 2r-rs 1.4 × as long as 1r-rs, joins Rs at the level of apex of pterostigma; 6-Rs in apical part sharply incurved toward the front edge of the wing; cell 3r 4.8 × as long as wide, 0.39 × as long as fore wing; 2-M as long as Rs+M; 3+4-M sharply incurved and s-shaped basally; 5-M 1.3 × as long as 3r-m; 1-Cu 1.1 × as long as 2-Cu; 1m-cu strongly curved towards the wing apex; 2m-cu s-shaped. Hind wing with 1-Rs 1.5 × as long as 2-Rs; r-m short; 1-M strongly s-shaped; proportions of veins 1-Cu, cu-a, 2-A1 differ significantly in left and right wings and thus cannot be considered reliable characters; m-cu not preserved in any of the wings. Ovipositor needle-shaped, thin, has uniform thickness throughout the length behind the abdominal base; length of preserved part of ovipositor equal to 1.1 of body length or 1.9 of fore wing length.

Measurements (in mm): body length 21.1; head height 3.2, dimensions of eye 1.3x0.8, approximate length of antenna 7.5; length of preserved part of the ovipositor 23.7 (from the base of the lancet) or 19.9 (from the top of the abdomen). The length of the fore wing is 13.6, the width is 3.4.

Comparison. The new species differs from K. macrura by absence of regular sclerotized incisurae on the ovipositor, wider pterostigma, location of 2r-rs, shape of 6-Rs and 3+4-M, shape of 1-M in the hind wing, and the large size.

Remarks. The new species does not have one of the striking characters of Kulbastavia macrura , i.e., the regularly dark sclerotized incisurae on the ovipositor ( Rasnitsyn, 1968). Nevertheless, the sum of its other features classify this specimen as closest to Kulbastavia , rather than to any representative of Anaxyelidae (presence of a very long ovipositor, the shape of the antennae, the sclerotized pterostigma, long 1-Rs, Rs+M, 5-M, shape of cells 1r, 2r, 3r, 2+3rm, 1mcu, large size of the body). The establishing of a new genus based on a singular feature, even more so that it is observed exclusively in the representatives of one gender, appears to be insufficiently substantiated. Also, it is noteworthy to mention that in both K. grandis and K. macrura the sculpture of the thorax is almost not preserved. It is quite possible that this is simple coincidence; however, it might be evidence of weak sclerotization of the mesonotum in representatives of this genus.

Vein 6-Rs on one of the wings bears a small aberrant antrorse vein stub. There is no such vein on the other wing, and it is also unique among other families of the Hymenoptera . It is evident that in this case we deal with a minor deformity. In the same wing, 3r-m is significantly curved, while in the other wing, this vein has a normal shape. Poor preservation of this area of the wing does not allow certainty as to whether this is the intra-vitum condition or a trace of post-mortem deformation.

Regarding the length of the fore wing (13.6 mm), dimensions of the body, and length of the ovipositor, the new species is the largest representative of Anaxyelinae . Among Anaxyelidae , only an undescribed Kempendajinae from Bon-Tsagaan (PIN, no. 3559/4458), is larger (wing length of 19.2 mm).

Figures

FIGURE 3. Kulbastavia grandis sp. nov., holotype: PIN, no. 2997/5000: A. habitus draw, B. reconstruction of wings. Karatau; Kazakhstan, Upper-Middle Jurassic. Scale bar 5 mm.

FIGURE 4. New species of Anaxyelidae from Karatau: A. Brachysyntexis tenebrosa sp. nov., holotype PIN, no. 2066/3344, B. Brachysyntexis tigris sp. nov., holotype: PIN, no. 2997/648, C—Kulbastavia grandis sp. nov., holotype: PIN, no. 2997/5000. Karatau; Kazakhstan, Upper-Middle Jurassic. Scale bars 5 mm.