Pareumenes (Nortonia) caoduong, Nguyen, 2020

Nguyen, Lien Thi Phuong, 2020, A new Vietnamese species and a key to the Oriental species of Pareumenes (Nortonia) de Saussure, 1855 (Hymenoptera: Vespidae: Eumeninae), Raffles Bulletin of Zoology 68, pp. 588-594 : 590-592

Pareumenes (Nortonia) caoduong , new species

( Figs. 1–9 )

Material examined. Holotype, female, pinned (deposited in IEBR), labelled “ VIETNAM: Cao Duong, Yen Thuan, Ham Yen , Tuyen Quang, Cham Chu NP, way to waterfall, 22°17′32.5″N 104°59′28″E, 15.v. 2019, 643 m, Nguyen T. P. Lien, Truong X. Lam, Nguyen Q. Cuong & Mai V. Thai” . Paratype (deposited in IEBR): 1 female, same data as holotype .

Diagnosis. This species can be distinguished from other species of subgenus Nortonia of the genus Pareumenes by the following combination of characters: Head in frontal view slightly wider than high. Body with coarse punctures; clypeus flat in the middle part, in lateral view convex from basal half, then straight to apical margin, apical emargination not so deep; vertex with depression behind posterior ocelli, with two foveae placed inside V-shaped carina; distance from posterior ocelli to apical margin of vertex 2.4 times distance from posterior ocelli to inner eye margin; lateral sides of propodeum shallowly emarginate at apex; metasoma petiolate in dorsal view with strongly projecting spiracles at about one-third of the length of the petiole basally, in lateral view abruptly produced near base, then depressed and gradually convex to near apical margin; apical margins of all terga not raised; forewing with parastigma slightly longer than stigma measured along ventral part. Clypeus with irregular yellow mark in the middle; tergum I with two large yellow spots at lateral side near apex, terga II–VI black except a short narrow yellow band at apical margin of tergum III medially. Description. Female ( Fig. 9 ). Body length 19.8–20 mm (holotype 19.8 mm); forewing length 18.5–18.7 mm (holotype 18.5 mm). Head in frontal view subcircular, slightly wider than high, about 1.1 times as wide as high ( Fig. 1 ). Vertex with slightly swollen area around ocellus, with depression behind posterior ocellus ( Fig. 2 ), with two cephalic foveae placed inside a V-shaped carina, close to each other. Distance from posterior ocelli to apical margin of vertex about 2.4 times distance from posterior ocelli to inner eye margin ( Fig. 2 ). Gena thick, wider than eye, in lateral view 1.2 times as wide as eye at ocular sinus. Occipital carina complete, present along entire length of gena. Inner eye margins slightly convergent ventrally, in frontal view nearly equal from each other at vertex as at clypeus. Clypeus flat in the middle part, disc of clypeus in lateral view weakly convex at basal half, then almost straight to apical margin, in frontal view nearly 1.2 times as high as wide ( Fig. 1 ), with basal margin strongly convex medially and almost touching antennal sockets; apical margin emarginate medially, forming sharp tooth on each lateral side ( Fig. 1 ); width of emargination much less than ⅓ width of clypeus between inner eye margins. Mandible with prominent five teeth, the first and second teeth from base denticle at inner margin. Antennal scape long, about 4.5 times as long as its maximum width; flagellomere I 2.0 times as long as wide, flagellomeres II–IV slightly longer than wide, flagellomeres V–VIII as long as wide, flagellomere IX wider than long, terminal flagellomere bullet-shaped, longer than wide.

Mesosoma longer than wide in dorsal view ( Fig. 3 ). Pronotal carina strongly raised throughout, reaching ventral corner of pronotum. Mesoscutum in lateral view weakly convex ( Fig. 4 ), in dorsal view almost as long as wide between tegulae, with prescutal furrows near apical margin ( Fig. 3 ). Disc of scutellum slightly convex, with a short medial longitudinal depression at base, in lateral view at the same level of apical margin of mesoscutum. Metanotum convex, sloping down to apical margin. Propodeum deeply excavated medially at apex, with the excavation wide, about one-third the width of propodeum, basal triangular area with longitudinal basal fovea, with median carina runs from half of the length of propodeum to apical margin ( Fig. 5 ), lateral side shallowly emarginate at apex; border between dorsal and lateral faces sharply angled. Forewing with parastigma slightly longer than stigma measured along ventral part ( Fig. 8 ).

Metasomal tergum I in dorsal view 1.6 times as long as wide, with the strongly projecting spiracles at about one-third of the length of the petiole basally ( Fig. 6 ), in lateral view abruptly produced near base, then depressed and gradually convex to near apical margin ( Fig. 7 ), much narrower than tergum II, with a fovea near apical margin; tergum II in dorsal view nearly as long as wide; sternum II in lateral view gradually and slightly convex at basal two-third, then straight to apical margin ( Fig. 7 ).

Body covered with golden setae. Clypeus covered with sparse and strong punctures, each bearing a short seta, punctures at centre larger than at sides, space between punctures larger than puncture diameter except some punctures at middle with space between punctures smaller than puncture diameter, punctures near apical margin smaller but denser. Mandible with several shallow small punctures. Frons densely covered with coarse punctures. Vertex and gena with strong punctures, space between punctures smooth. Pronotum with punctures coarser than those on frons, spaces between punctures not raised, anterior face smooth. Mesoscutum densely covered with strong and flat-bottomed punctures except area between furrow with sparse punctures ( Fig. 3 ), punctures at margins sparser. Punctures on scutellum similar to those on mesoscutum. Punctures on metanotum larger than those on scutellum. Mesepisternum with punctures on upper dorsal part very coarse, space between punctures strongly raised to form reticulation, with strong and large punctures posterodorsally, several shallow and small punctures anteroventrally; border between posterodorsal and anteroventral parts indistinct. Metapleuron almost smooth. Propodeum with strong punctures and some large smooth area on dorsal surface, posterior surface with coarse punctures in between strong punctures, some transverse striations in the middle half at apex; lateral surface with striations and sparse punctures. Metasomal tergum I densely covered with dense and coarse punctures but punctures smaller than those on pronotum, punctures on tergum II much sparser and weaker than those on tergum I, punctures on terga III–V much smaller and weaker than those on tergum II; tergum VI with minute punctures; punctures on sternum II stronger and larger than those on sterna III–V, sternum VI with minute punctures.

Colour. Black; following parts yellow: an irregular mark at the middle of clypeus, large spot between antennal sockets, antennal scape beneath, two thin short bands at dorsal part of pronotum near pronotal carina (almost touching each other), apical margin of valvulae, two large spots at lateral sides near apex of tergum I, a short apical band on tergum III medially. Legs almost black except some brown parts at apical half of middle and hind tibiae. Wings infuscate, veins dark brown.

Male. Unknown.

Distribution. Vietnam (Northern part).

Etymology. The specific name refers to the type locality, Cao Duong, Tuyen Quang province of Vietnam; it is to be treated as a noun in apposition.

Remarks. This species comes close to Pareumenes taiwanus ( Sonan, 1937) in having coarse punctures on mesosoma and vertex, tergum I coarsely punctate, petiolate, gradually widening to apex, but can be distinguished from the latter by having clypeus with sparse and strong punctures, border between punctures smooth (vs. clypeus with coarse and dense punctures, border between punctures raised to form longitudinal reticulation in P. taiwanus), frontal view slightly wider than high (vs. as wide as high in P. taiwanus); vertex with two foveae close to each other (vs. vertex with a median fovea in P. taiwanus); lateral side of propodeum shallowly emarginate at apex (vs. lateral side of propodeum deeply emarginate at apex in P. taiwanus); and colouration: clypeus black with irregular yellow mark in the middle (vs. clypeus entirely yellow in P. taiwanus); two short and thin yellow bands on pronotum (vs. two large spots on pronotum in P. taiwanus); tergum II entirely black (vs. tergum II with a broad apical yellow band in P. taiwanus).

Figures

Figs. 1–6. Pareumenes caoduong, new species, holotype, female. 1, Head in frontal view; 2, Vertex in dorsal view; 3, Mesosoma in dorsal view; 4, Mesosoma in lateral view; 5, Propodeum in posterior view; 6, Tergum I in dorsal view. Scale = 1 mm.

Figs. 7–12. Pareumenes caoduong, new species, holotype, female (7–9). 7, Metasomal terga in lateral view; 8, Forewing; 9, Habitus. Pareumenes quadrispinosus acutus Liu, 1941, female (10–12). 10, Head in frontal view; 11, Forewing; 12, Habitus. Scale = 1 mm.