Xyelocerus abruptus Sun, Rasnitsyn, Zhuang & Shih, 2024

Sun, Chenhui, Rasnitsyn, Alexandr P., Wedmann, Sonja, Zhuang, Jialiang, Shih, Chungkun, Ren, Dong & Gao, 2024, Revisions * new taxa * and venation transformations of the sawfly family Blasticotomidae sensu lato (Hymenoptera: ºenthredinoidea) highlight the evolution of the basal Hymenoptera, Zoological Journal of the Linnean Society 202 (1), pp. 1-19 : 3

Xyelocerus abruptus Sun, Rasnitsyn, Zhuang & Shih , sp. nov.

( Fig. 1 )

http://zoobank.org/ urn:lsid:zoobank.org:act:4F22E9A3-FA40-459D-A8EE-A21B31CEE004

Diagnosis: Forewing with pterostigma sclerotized. Vein Sc present* forming kink to R and touching it in a point at level of 1-M base* or preserving dot-like short Sc 2 * and with Sc 1 oblique crossvein-like. 1-M bent before 1-Rs* five times as long as 1-Rs. Rs+M* 1m-cu* and 2-Cu of subequal length.

Etymology: The species name is derived from the Latin word ‘abruptus’* meaning suddenly steep* referring to the kink of Sc before touching R.

Material: Holotype * CNU-HYM-NN2022311 . Paratypes: CNU-HYM-NN2022312 ; CNU-HYM-NN2022313 ; CNU-HYM-NN2022314 ; CNU-HYM-NN2022315 (poorly preserved* sex unknown); CNU-HYM-NN2022316 (poorly preserved* sex unknown) .

Locality and horizon: Latest Middle Jurassic (late Callovian)* Jiulongshan Formation; Daohugou Village * Wuhua Township* Ningcheng County * Chifeng City * Inner Mongolia * China.

Description ( Fig. 1A–C ): Holotype * CNU-HYM-NN2022311. Very incompletely preserved. Sex unknown. Body length 12.8 mm * with abdomen partly preserved.

Head: Temples convex* extending lateral beyond eyes. Antenna incompletely preserved.

Forewing: Left forewing length 11.4 mm as preserved. Pterostigma fully sclerotized. Sc forming kink and touching R in a point at level of 1-M base; Sc 1 oblique ( Fig. 1C ). Two adventitious ‘1-Rs’ present before true one in left forewing* forming two small cells. 1-M (1.88 mm) straight and ~6.2 times as long as 1-Rs (0.30 mm). Vein M+Cu slightly bent. Crossvein 1r-rs shorter than 2-RS. Cell 1r small* 1mcu large* Rs+M* 1m-cu and 2-Cu of subequal length.

Legs: Left hind tibia narrow* 5.3 mm long.

Paratype CNU-HYM-NN2022312 ( Fig.1D, E )

Sex unknown. Very incompletely preserved* preserved similar to holotype.

Paratype CNU-HYM-NN2022313 ( Fig. 1F, G )

Female. Generally similar to holotype. Head and thorax dorsally coarsely punctated. Adventitious ‘1-Rs’ present before true one in right forewing ( Fig. 1G )* forming a small cell. Body length 19.9 mm * right forewing length 15.6 mm * ovipositor length 3.4 mm.

Paratype CNU-HYM-NN2022314 p/c

(part and counterpart) ( Fig.1H, I )

Sex unknown. Body and wings very incompletely preserved. As preserved* similar to holotype. Adventitious ‘1-Rs’ present before true one in right forewing ( Fig. 1I )* forming a small cell. Right forewing length 14.8 mm as preserved.

Figures

Figure 1. Xyelocerus abruptus. A–C* dorsal view (A)* line drawing (B)* and vein Sc in left forewing (C) of the holotype of CNU- HYM-NN2022311* sex unknown.D* E* dorsal view (D) and vein Sc in right forewing (E) of the paratype of CNU-HYM-NN2022312* sex unknown. F* G* ventral view (F) and vein Sc in right forewing (G) of the paratype of CNU-HYM-NN2022313* female. H* I* ventral view (H) and vein Sc in right forewing (I) of the paratype of CNU-HYM-NN2022314p. Scale bars: 2 mm in A* B* F* H; 1 mm in C–E* G* I.