Scleroxyela daohugouensis, Zheng, Yan, Hu, Haiyan, Chen, Dong, Chen, Jun, Zhang, Haichun & Rasnitsyn, Alexandr P., 2021

Zheng, Yan, Hu, Haiyan, Chen, Dong, Chen, Jun, Zhang, Haichun & Rasnitsyn, Alexandr P., 2021, New fossil records of Xyelidae (Hymenoptera) from the Middle Jurassic of Inner Mongolia, China, European Journal of Taxonomy 733 (733), pp. 146-159 : 153-156

Scleroxyela daohugouensis gen. et sp. nov.

urn:lsid:zoobank.org:act:D2420568-B709-4DF1-BCD7-B96E60034D5E

Figs 4–5

Diagnosis

As for genus.

Etymology

The specific name is derived from Daohugou village, where the type specimen was found.

Type material

Holotype, female, NND0185 ; NIGP.

Locality and horizon

Daohugou Village, Wuhua Township, Ningcheng County, Chifeng City, Inner Mongolia , China: Jiulongshan Formation, Middle Jurassic (Callovian-Bathonian boundary).

Description

Female sawfly in ventral view with incomplete wings and body. Head large and subovate, with gena long and possibly postgenal bridge present, no eyes and ocelli visible in ventral view. Antenna ca 1.8 times as long as the width of head, scape with only apical part visible, obviously wider than pedicel, third segment approximately twice as thick as flagellum and distinctly longer than the latter.

Thorax obviously wider than head; propleurae smooth and relatively small, notauli well impressed, incompletely preserved, medial mesoscutal line long and deep; prosternum large, butterfly-like.

Forewing with pterostigma lanceolate and very narrow; costal area obviously widened proximad of base of Rs; Sc bifurcate, Sc1 connecting C beyond origin of Rs, Sc2 short and subvertical, meeting R before origin of Rs, Sc1 at least twice as long as Sc2; 1-Rs half as long as 1-M; crossvein 1r-rs subparallel to 2r-rs and 0.7 times as long as it; distance of 2r-rs to apex of pterostigma as long as distance from 2r-rs to 1r-rs; M+Cu almost straight; Rs+M approximately five times as long as 1-Rs; 3-Rs arching; 1m-cu not

preserved but as restored about as long as 2-Cu and half as long as 3-Cu; 2m-cu as long as M between it and 3r-m, inclined toward wing base; length proportion of cells 1r: 2r: 1mcu: 2mcu= 2.5: 1.3: 2.7: 2.8.

Hindwing partly preserved, with 1-Rs short but distinct, 1-Cu as long as 1-M and 1r-m combined, cu-a about half as long as 1-Cu and 2-Cu.

Foreleg short with coxa, trochanters, femora, tibiae and incomplete tarsi seen. Forecoxae trapezoidal, ca 0.7 times as long as wide, trochanter ca 1.4 times as long as wide, foretibia with two spurs visible, one long and one short. Midleg with coxa large and trapezoidal, trochanter small and rectangular, femur slightly thicker than fore femur, tibia with one preapical spur visible, tarsus complete, with basitarsus shorter than three following segments combined, fifth segment about as long as third and fourth segments together, claw small, arolium distinct. Hindleg with coxa large and trapezoidal, trochanter small, wider than long, trochantellus not much smaller than trochanter, femur longer and wider than in midleg, tibia ca 0.7 times as long as femur and half as long as femur in width, with one preapical spur and socket of another more basal one visible and with two short apical spurs, tarsus longer and wider than in midleg, with fifth segment short or, rather, incompletely preserved, others similar to mid tarsus.

Abdomen with seven visible segments, ovipositor well developed, with wide sword-shaped sheath, gradually tapering toward narrowly rounded apex, length ratio of valvifer 1: valvifer 2: valvula 3 = 0.5: 1.6: 2.4.

Measurements

Body length excluding ovipositor sheath 11.5 mm. Head width 2.1 mm, length 1.5 mm. Antennae not shorter than 4.3 mm, third antennal article ca 2.1 mm. Incomplete forewing length as preserved ca 11.1 mm, maximum width ca 4.5 mm. Length of thorax 3.6 mm, abdomen 6.5 mm. Ovipositor sheath length 2.2 mm.

Figures

Fig. 4. Photograph of Scleroxyela daohugouensis gen. et sp. nov. Holotype, NND0185. Ruler unit (top right): 1 mm.

Fig. 5. Line drawings of Scleroxyela daohugouensis gen. et sp. nov. A. Habitus, holotype. B. Right forewing. C. Right hindwing. Symbols as in Fig. 3 except: ar = arolium; bpge? = possible postgenal bridge; ge = gena; mmsl = medial mesoscutal line; osp = attachment site of tibial spur; pl 1 = propleuron; sp = tibial spur; st = prosternum; tl = hind trochantellus. Scale bars: 1 mm.