Sinopalaeodermata concavum Xiong, Engel & Ren, 2021

Xiong, Shurong, Engel, Michael S., Xiao, Lifang & Ren, Dong, 2021, New archidermapteran earwigs (Dermaptera) from the Middle Jurassic of Inner Mongolia, China, ZooKeys 1065, pp. 125-139 : 125

Sinopalaeodermata concavum Xiong, Engel & Ren sp. nov.

Figures 4 , 5

Diagnosis.

The new species can be distinguished from the type species, Sinopalaeodermata neimonggolense (note that the name Sinopalaeodermata is neuter, not feminine, as dérmata is the neuter nominative plural of dérma; and given that the specific epithet is adjectival it must still agree in gender with the generic name) by the relatively straight apical margin of the penultimate sternum (in S. neimonggolense the penultimate sternum has a concave margin); the roughly reniform pronotum, with the anterior margin concave medially the posterior margin weakly convex, and lateral margins rounded (in S. neimonggolense the pronotum is approximately rectangular, with the anterior margin almost as wide as the posterior margin, and the lateral margins relatively straight and parallel to each other); the tegmina with a more pronounced concave arc marginally at the apex of Rs (in S. neimonggolense the margin is more sloping rather than deeply concave); and M does not extend to near the apex of CuA, with CuP terminating more proximal to CuA (even before the tangent with M) (in S. neimonggolense M terminates more proximally and CuP extends to the apex of CuA).

Holotype. A completely preserved female, CNU-DER-NN2021005C/P, deposited in the College of Life Sciences, Capital Normal University, Beijing, China.

Locality and horizon.

Jiulongshan Formation (Middle Jurassic); Daohugou Village, Wuhua Township, Ningcheng County, Inner Mongolia, China.

Description.

Adult female, preserved in both dorsal and ventral aspects. Total length as preserved (excluding antennae, cerci, and valvulae) about 18.02 mm. Body with sparse pubescence and punctate. Head medial length from clypeal apex to posterior border 2.08 mm, maximum width (across level of compound eyes) 2.27 mm, triangular. Compound eye large, ovate, located near posterior margin of head; compound eye length 0.91 mm; width between compound eyes 2.58 mm. Ocelli comparatively small. Cervix with large anterior and posterior cervical sclerites, anterior sclerite slightly larger than posterior sclerite. Pronotum approximately reniform, medial length 1.46 mm, maximum width 2.58 mm, anterior width 1.64 mm, posterior width 2.07 mm, anterior margin concave and posterior margin arched, lateral margins convexly rounded. Mesoscutellum large, elliptical, entirely exposed. Tegmina present, not truncated, length 6.73 mm, maximum width 2.55 mm, with medially sinuate anterior (lateral) margin and straight posterior (mesal) margin. Veins simple, Rs curved anterior margin, fading out just before margin; M simple, basally and apically straight, gently curved medially; Cu with two branches (CuA and CuP), CuP terminates proximal to CuA; A1 and A2 simple and straight, running parallel to each other and posterior margin, terminating apically (Fig. 4C ). Femora compressed and ventrally carinulate (Fig. 4D ); tibiae elongate, slender, and almost as long as femora; tarsi pentamerous, tarsomere IV slightly extending under base of tarsomere V (Fig. 5C ). Pretarsal claws present but not well preserved. Abdominal length as preserved (excluding cerci) 9.75 mm, maximum width 3.52 mm; all segments distinctly wider than long, lateral abdominal margins gently convex. Pygidium not evident. Ovipositor exposed, 2.84 mm long. Cerci as preserved only 2.9 mm long, with segments but not clearly preserved.

Etymology.

The specific epithet is taken from the Latin adjective concavus (meaning, “concave”), in reference to the more pronounced concave margin to the tegmina relative to the type species.

Figures

Figure 4. Holotype of Sinopalaeodermata concavum sp. nov. CNU-DER-NN 2021005 C. A Photograph of dorsal aspect B line drawing of dorsal aspect C dorsal view of right tegmen D anterior lateral (prolateral) view of left midleg. Scale bars: 4.0 mm (A, B); 0.5 mm (C, D).

Figure 5. Holotype of Sinopalaeodermata concavum sp. nov. CNU-DER-NN 2021005 P. A Photograph of ventral aspect B line drawing of ventral aspect C ventral view of right midleg and tegmen. Scale bars: 4.0 mm (A, B); 1 mm (C).