Parancistrocerus abyssicavus Li & Carpenter, 2019

Li, Tingjing & Carpenter, James M., 2019, Descriptions of eight new species of the genus Parancistrocerus Bequaert (Hymenoptera: Vespidae: Eumeninae), with a key to the Oriental species, Zootaxa 4551 (3), pp. 251-274 : 267-269

Parancistrocerus abyssicavus Li & Carpenter , sp. nov.

( Figs 38–43 )

Material examined. Holotype, 1♀, Thailand, Chaiyaphum TatToneNP Entrance to Pa Eang waterfall, 15°57.52′N, 101°54.442′E, 297m, Malaise trap, 26.X–3.XI.2006, Tawit Jaruphan leg., T687, deposited in QSBG . Paratype: 1♀, Thailand, Nong Bua Lampoo Phu Kao-Phu Phan Kham NP E. of grdn. 16°48.44′N, 102°36.959′E, 247m, Malaise trap, 5–12.VII.2006, Rakkiat Singhatip leg., T87, deposited in AMNH .

Diagnosis. This species can be easily distinguished from other members of Parancistrocerus by having T2 basally with a large deep cavity mesally ( Fig. 43 ).

Description. Female ( Fig. 38 ). Body length 6.0– 6.5 mm. Head as wide as long in frontal view ( Fig. 39 ); clypeus densely with setae, sparsely punctate, clypeal maximum width 1.27× its length, moderately convex basally to middle and more or less plattened at subapical part, apex emarginated forming two lateral teeth, apical width 1.18x distance between antennal sockets; inter-antennal area with longitudinal and strong carina; frons moderately swollen, deeply and densely punctate, and reticulate, punctures on vertex and tempora somewhat sparse than those of frons; cephalic foveae present, unobvious and just slightly bigger than surrounding punctures; interocular distance 1.38× greater on vertex than at clypeus; POL as long as OOL; distance between anterior and posterior ocelli 1.29× diameter of anterior ocellus; occipital carina complete.

Median area of anterior face of pronotum polished ( Fig. 40 ), with small and totally merged foveae mesally; laterally coriaceous, with dense setae and few scattered punctures; pronotal carina absent dorsally, present and strong laterally; posterior and lateral sides of pronotum, mesoscutum and scutellum strongly and densely punctate and reticulate, these punctures relatively bigger and deeper than those on head; mesoscutum somewhat swollen mesally, median length as long as its maximum width; scutellum medially with longitudinal groove; metanotum with sparse punctures; mesopleuron closely punctate except large area of epicnemium and posterior margin with pubescence; epicnemial carina present; metapleuron pubescence; dorsal face of propodeum coarsely punctate, interspaces between punctures with reticulate carinae, and forming horizontal area behind midline of metanotum ( Fig. 41 ); posterior face of propodeum concave, with median carina and dense setae, punctate on upper part and with thin transverse striae on lower part; lateral sides of propodeum strongly punctate, interspaces between punctures mostly carinate; superior carina of propodeum well-developed and distinct especially at top, clearly separating horizontal dorsal face from posterior face, submarginal carina moderately projecting as lobe above propodeal valvula. Tegula smooth with minute punctures, rounded posteriorly, emarginated adjoining parategula and almost extending to apex of latter posteriorly.

T1 with regular, strong transverse carina separating vertical face from dorsal face, transverse carina 0.81× as wide as dorsal horizontal face; vertical anterior face distinctly shorter than dorsal horizontal face, moderately with setae, and with few weak scattered punctures; dorsal face of T1 gradually swelling from base to apex, 1.42× as wide as its median length, densely punctate but punctures sparser, shallower and smaller than those on head and mesosoma, and with about 3–4 irregular rows of punctures at apical band; punctures of T2 similar to those of T1, T2 with a big and deep cave at median base ( Fig. 43 ), with about 3–4 irregular rows of punctures at apical band, 1.08× as wide as its median length; maximum width of T2 1.13× that of T1, T2 not reflexed at apex, with apical margin normal, not prolonged mesally; S2 slightly lowered at median base ( Fig. 42 ); following metasomal segments normal.

Black. Following parts yellow: two lateral arched spots at base of clypeus (two spots connected in another specimen), basal spot on mandible, median spot on lower frons, apical spot in ocular sinus, a band on tempora, ventral side of scape, median and wide band on dorsal surface of pronotum, circle band of tegula, parategula, metanotum, apical spots on fore and mid femora, outer long band on all tibiae, wide apical band on T1, somewhat narrowed at sides; apical and wavy bands on T2 & S2; two small spots at apex of clypeus, and apical and thin bands (without apical band in another specimen) of both T3 and T4 brown yellow; mandible mostly, antenna ventrally except scape, tegula except yellow band, tibiae excluding yellow band, and all tarsi ferruginous to dark ferruginous.

Male. Unknown.

Distribution. Thailand.

Etymology. The specific name abyssicavus is derived from two Latin words: abyss (=deep) and cavus (=cave), referring to the deep cavity of T2.

Remarks. The Nearctic species P. vagus (de Saussure) similarly has T2 basally with a large deep cavity mesally, which Bohart (1952) referred to as a median entrance to the acarinarium.

Figures

FIGURES 38–43. Parancistrocerus abyssicavus sp. nov., holotype, ♀. 38. Habitus, dorsal view; 39. Clypeus; 40. Pronotum, dorsal view; 41. Propodeum, dorsal view; 42. S2, ventral view; 43. T2–T3, dorsal view.