Parancistrocerus lamnulus Li & Carpenter, sp. nov.

(Figs 7–13)

Material examined. Holotype, 1♂, China, Yunnan prov., Puer City, Yuan Cunty, Mengda Town, Yiwendao Village, 24°00'09.4"N, 100°51'46.5"E, 11.VI.2017, Yan Peng, No. 1004108 (CQNU).

Diagnosis. This species can be easily distinguished from other members of Parancistrocerus by having an apical prolongation of T3 formed by a narrowly separated lamella deriving from the ventral T3 apex (Fig. 13).

Description. Male (Fig. 7). Body length 6.0 mm. Head longer than wide in frontal view; clypeus (Fig. 8) moderately punctate, clypeal maximum width 0.86× its length, somewhat convex, apex moderately emarginated forming two lateral teeth, apical width 1.19× distance between antennal sockets; inter-antennal area with longitudinal carina; frons coarsely punctate and distinctly reticulate, punctures on vertex and tempora sparser and smaller than those of frons; interocular distance on vertex 1.96× that at clypeus; POL 1.29× OOL; distance between anterior and posterior ocelli as long as diameter of anterior ocellus; occipital carina complete; A11 slightly wider than long; apex of A13 approaching base of A11.

Median sloping area of anterior face of pronotum polished, with two small and separated foveae mesally (Fig. 9); lateral sides of anterior face of pronotum with coarse punctures; pronotal carina absent dorsally; pronotum, mesoscutum and scutellum coarsely punctate, these punctures similar to those on vertex; median length of mesoscutum as long as its maximum width; scutellum medially without an indistinct and longitudinal groove; metanotum with coarse punctures, interspaces carinate and bluntly dentiformed; mesopleuron coarsely punctate and reticulated except large area of epicnemium and posterior margin with pubescence; epicnemial carina present and strong; metapleuron coriaceous and without pubescence; dorsal face of propodeum coarsely punctate and forming short horizontal area behind midline of metanotum (Fig. 10), punctures large, shallow, flat bottomed and interspaces with reticulate carinae; posterior face of propodeum concave, with median longitudinal carina, and thin, dense and transverse striae; lateral sides of propodeum dull and sparsely punctate, interspaces between punctures somewhat carinate; superior carina of propodeum not developed and just somewhat carinate at top, submarginal carina well-developed as lobe above propodeal valvula. Tegula smooth with minute punctures, somewhat rounded posteriorly, emarginate adjoining parategula and almost reaching apex of latter.

T1 with strong transverse carina separating vertical face from dorsal face (Fig. 10), transverse carina 0.82× as wide as dorsal horizontal face; vertical anterior face about half of dorsal horizontal face, moderately setaous, coriaceous, without scattered punctures, dorsal face 1.80× as wide as its median length, coarsely reticulate and punctate, interspaces between punctures obviously carinate, similar to those on frons, and without regular rows of punctures at yellow band; T2 (Fig. 12) evenly punctate, punctures slightly sparser than those of T1, interspaces almost equal to diameter of puncture, T2 bell-formed, laterally not concave basally, median part not swollen, without cave at median base, without rows of punctures at apex, 1.83× as wide as its median length; maximum width of T2 1.56× that of T1, T2 not reflexed at apex, with apical margin normal, not prolonged mesally; S2 strongly lowered basally and then widely depressed (Fig. 11); punctures of T3 denser than those of other metasomal parts, and apex of T3 with narrow and independent lamella deriving from apex below T3 and forming indistinct prolongation mesally (Fig. 13); S3 transversely elongated at the median apex (Fig. 11); other metasomal segments normal.

Black. Following parts yellow: clypeus (Fig. 8), mandible excluding apical and outer margins, ventral side of scape, and spots on all tibiae and apexes of fore and mid femora; small spot on upper tempora, median, interrupted and wide band on dorsal surface of pronotum, posterior outside of tegula, apex of parategula, metanotum, submarginal carina, thin apical bands of T1–T2, and thin, interrupted apical band of S2 brownish yellow.

Female. Unknown.

Distribution. China (Yunnan).

Etymology. The specific name lamnulus is derived from the Latin word lamnula (=lamellate), referring to the apical lamella of T3.