Sinoparathyrea robusta Pan, Chang & Ren, sp. nov.

Sinoparathyrea robusta Pan, Chang & Ren, sp. nov.

(Figs. 8, 9, 12, 13)

Type specimen. Holotype, male, CNU-COL-NN2010410 PC (part and counterpart of one fossil specimen), housed in the Key Lab of Insect Evolution & Environmental Changes, Capital Normal University, Beijing, China.

Locality and horizon. Daohugou Village, Middle Jurassic Jiulongshan Formation, Ningcheng County, Inner Mongolia, China.

Etymology. The species name is derived from the Latin word “ robustus ”, referring to its wider body.

Diagnosis. Body wide; pronotum wider, about 1.65 times as wide as long, anterior pronotal margin straight, posterior margin slightly bisinuate; Elytra 3.0 times as long as wide, disc with nine distinct longitudinal striae, the 6th and 7th striae fading out at 1/5 of elytron length from apex; the first ventrite 2.5 times as long as the second one.

Description. Body medium sized, 13.6 mm long and 6.7 mm wide, subcylindrical; pronotum slightly narrower than elytra; surface of body with uniform, small, rounded and dense punctures (Figs. 8, 12).

Head: frontovertex convex, surface with granulose and coarse punctate dorsally; eyes relatively small, oval (Fig. 8).

Antennal cavities separated, the distance between them wider than diameter of cavity, antennae short, can not reach the posterior angle of pronotum, right one with 6 preserved segments, the left with 8 preserved segments, antennomere 1 stout, 2 shorter than 1, with length and width subequal, 3 longer than 2, more slender, 4−8 serrate (Figs. 9, 13).

Pronotum about 1.65 times as wide as long, the widest part of pronotum at its base; anterior pronotal margin straight, posterior margin slightly bisinuate; lateral margins weakly arched at anterior 3/4, then arcuately expanded to posterior margin, basolateral angles acute; integument of pronotum with feeble transverse striae formed by coarse punctates. Scutellum triangular, wider than long, lateral margins arcuately concave, posterior apex acuminate (Figs. 8, 12).

Elytra 3.0 times as long as wide, the widest part at the middle; lateral margins weakly arcuate in anterior 2/3, then somewhat narrowed to obtuse apex; disc with 9 distinct longitudinal striae, the 6th and 7th striae fading out at 1/5 of elytron length from apex; disc with 5 oblong spots: one located at the posterior 2/3 of disc across the forth and the ninth striae; the other four near the inner margin between the first and the sixth striae (Fig. 8).

Ventral surface reticulate, finely punctate; prosternal process subparallel, lateral margins slightly converging posteriorly to obtuse apex, process narrower than procoxae; procoxae, mesocoxae rounded, distance between procoxae subequal with distance between mesocoxae; metepisternum quadrate; paracoxal suture straight; metacoxae transverse, short laterally, posterior margin arcuately emarginated; abdominal ventrites with finely, rather dense punctures, which formed into faint rugae, the first ventrite 2.5 times as long as the second one; ventrites 2−3 subequal in length, 4 shorter than 3, 5 broadly rounded at apex, 1.4 times longer than the previous one (Figs. 9, 13).

Legs: pro-, mesotrochanters trapeziform, metatrochanters round triangular; femora subfusiform; tibiae feebly arcuate, slender.

Male genitalia: parameres steeply narrowing to separately acuminate apices; medium lobe robust, with acuminate apex (Fig. 9).

Dimensions. Body length/body width/elytron length, in mm: CNU-COL-NN2010410: 13.6/6.7/10.1.

Remarks. Among all the species of the fossil subfamily Parathyreinae, Sinoparathyrea robusta sp. nov. is the first fossil with the description of the genitalia. It has the similar medium lobe with the species Agrilus betulanigrae Macrae, 2003, whose parameres subquadrately expanded in apical half, wider than the parameres of the species Sinoparathyres robusta sp. nov..