Discoelius emeishanensus Zhou & Li, 2013

Zhou, Xin, Chen, Bin & Li, Ting-jing, 2013, Two new species of the genus Discoelius Latreille (Hymenoptera, Vespidae, Eumeninae) from China, with a key to the Chinese species, Journal of Hymenoptera Research 32, pp. 45-54 : 48-50

Discoelius emeishanensus Zhou & Li sp. n. Figs 5-10

Material examined.

Holotype, ♀: China, Sichuan Prov., Leshan City, Emeishan Country, Gaoqiao Town, Yanshi Village, 29°30'14"N, 103°25'35"E, 551 m, 11. VIII. 2011, Tingjing Li (CQNU).Paratype: 1♂, the same as holotype (CQNU).

Description.

Female body length 15.0 mm, forewing length 12.0 mm. Black; with the following parts yellow or orange yellow: a marking on mandibular base, apex of clypeus, a small spot just above antennal socket ( Figs 6, 7 ), a line on the anterior face of fore tibia, narrow apical bands on terga 1-2 ( Figs 5, 10 ); anterior face of antennal scape with a deep brownish line.

Head: In frontal view, head subcircular; punctures mostly dense and coarse; mandible stout, not long, its apex sharply pointed and slightly curved inward, inner margin with four wide teeth, outer surface with four longitudinal carinae; clypeus wider than long, with short white setae and irregular strong punctures (somewhat reticulate), its apical margin truncate ( Fig. 6 ), in profile, not concave; frons weakly concave in the middle, one strong vertical carina just above the clypeus and the carina distinct in the upper about one-half of clypeus ( Fig. 6 ); scape of antenna somewhat shining, densely covered with minute punctures, flagellum not shining and with microscopic punctures, antennal article 3 longer than article 4, articles 4-10 wider than long and apical width about 1.2 times basal width, respectively; in profile, gena very wide, gradually narrowing towards the base of mandible and the narrowest near the base of mandible.

Mesosoma: From above, length of mesosoma about 2 times its width, and the whole mesosoma with white short appressed pubescenses and coarse punctures; pronotum with one continuous ridge extending laterally to fore coxa; one weak carina between the notaulices; scutellum and metanotum strongly punctate, with longitudinal, elongate wrinkles and without median furrow; propodeum shining, with lateral carina and sparsely short setae, dorsal and posterior faces rugosely striate to reticulate, lateral face shining, without punctures and setae; the setae on the mid tibia denser than the femur and the apical width about 2 times basal ones; the mid tarsal 1 dumpy and the hind tarsal 1 slender; the length of the mid tarsal 1:2:3:4 ≈ 4:1:1:1, and ≈ 20:4:2:1 in hind tarsus.

Metasoma: Length of metasomal segment 1 more than 2 times its apical width; tergum 1 with big and sparse punctures and white short setae, in profile, the anterior slope rather steep ( Fig. 8 ); the length of tergum 2 about 1.1 times apical width, terga 2-3 apically with developed reflexed lamellae, respectively; the other terga without apical lamellae, with weaker and sparser punctures ( Fig. 10 ); the apical margin of terminal metasoma triangle.

Male ( Figs 7, 9 ). Differs from the female as follows: body length 12.0 mm, forewing length 8.0 mm; mandible with three teeth, of which the apical one very long and the yellow marking bigger, almost covering the wholly outer surface of mandible; clypeus almost wholly yellow ( Fig. 7 ); the length of antennal flagellum 1 about 1.8 times apical width and gradually widening from base; flagellum 2 about 1.2 times width and not widening from base; flagellums 3-7 as long as apical width; antennal article 13 almost black, dull and small, folded beneath ( Fig. 9 ); outer face of fore femur with a very broad yellow line, and mid femur apically with a small yellow markings; mid tibia sparsely with short white setae, and hind tibia with long goldenish denser setae; the length of mid tarsal 1:2:3:4 ≈ 5:1:1:1, and ≈ 24:6:2:1 in hind tarsus, the length of hind tibia about 1.5 times mid tibia; in dorsal view, the length of metasomal tergum 1 about 1.2 times width and the length of tergum 2 about 0.8 times width, the setae on sterum 2 denser than those on tergum 2; terminal metasoma subcircular, punctures bigger and denser than those on tergum 2, setae shorter and sparser and apical margin brownish.

Remarks.

This species can be distinguished from the similar Discoelius zonalis (Panzer, 1801) and other members of the genus by the combination of the following characters: propodeum shining, sparsely with short setae; in male mandible with three teeth, of which theapical one very long, in female mandible with four teeth; scutellum and metanotum without obviously median furrow; terga 2-3 with a developed reflexed apical lamella, respectively ( Fig. 10 ); tegula entirely black; in male, outer face of fore femur with a broad yellow line; metasomal tergum 1 with big punctures.

Distribution.

China (Sichuan).

Etymology.

The specific name emeishanensus is the Neolatin adjective, which refers to the region from which the type specimens were collected.

Key to the Chinese species of the genus Discoelius

1	Large species: body length more than 17.5 mm and forewing length more than 15.0 mm in female; clypeus basally distinctly emarginate; between the notaulices shining apically, not punctate and without carina; metasomal tergum 2 basally with one smooth area	Discoelius nigriclypeus Zhou & Li, sp. n.
-	Small species: body length less than 15.0 mm and forewing length less than 14.0 mm in female; clypeus basally indistinctly emarginate; between the notaulices usually not shining, with punctures or carina; metasomal tergum 2 basally without one smooth area	2
2	Clypeus slightly emarginate apically; anterior slop of metasoma tergum 1 rather gentle; tergum 2 with a very narrow “neck” and entirely black ( Yamane 1996)	Discoelius longinodus Yamane
-	Clypeus usually widely rounded or truncated apically; anterior slop of metasoma tergum 1 steep; tergum 2 without narrow “neck” and usually with yellow apical band	3
3	Metasomal terga 2-4 with a reflex apical lamella, respectively	4
-	Metasomal terga 2-3 usually with a lamella, respectively (sometimes just tergum 2 with lamella)	5
4	Propodeum with lateral ridges and lateral face with superficial and irregular large punctures in the upper portion; clypeus and mesosoma usually entirely black; stigma of forewing brown to dark brown ( Yamane 1996)	Discoelius wangi Yamane
-	Propodeum without lateral ridges and lateral face weakly reticulated; usually two-third of clypeus apicaly yellow and mesosoma with rich yellow markings; stigma of forewing amber yellow ( Yasumatsu 1934; Yamane 1996)	Discoelius esakii Yasumatsu
5	In female, mandible with four teeth; in male, mandible with three teeth and the apical teeth very long; scutellum and metanotum without obviously median furrow; tegula usually entirely black; the punctures on the metasoma tergum 1 bigger and sparser, sternum 2 without yellow apical band; in male, outer face of fore femur with a broad yellow line	Discoelius emeishanensus Zhou & Li, sp. n.
-	Mandible with two or three teeth in female and three or four teeth in male, the apical teeth not long in both sexes; scutellum and metanotum with median furrow; tegula usually with yellow or brownish colour; the punctures on the metasoma tergum 1 smaller and denser, sternum 2 usually with yellow apical band; in male, outer face of fore femur usually entirely black	6
6	In frontal view, face including clypeus flattened in female; frons, clypeus, mesoscutum and scutellum densely with longitudinal carinae in the female; male antennal articles 8-10 distinctly with tyloids covering their lower faces extensively; terminal article stumpy, in profile slightly longer than breadth, and obliquely truncated on apical margin (Kim, 2005)	7
-	In frontal view, face including clypeus not flattened in female; frons, clypeus, mesoscutum and scutellum densely with punctures, which only partially form carinae and reticulae, in the female; in male antennal articles 10 ventrally and apical part of article 9 with weak and small spot-like tyloids; terminal antennomere slender, in profile distinctly longer than breadth, with apical margin somewhat rounded (Kim, 2005)	Discoelius zonalis (Panzer)
7	Vertex without yellow line; mesosoma black, except pronotum with a pair of yellow dots	Discoelius dufourii dufourii Lepeletier
-	Vertex with a pair of short oblique yellow line; pronotum, tegula, mesepisternum, scutellum and metanotum with yellow markings, respectively	Discoelius dufourii manchurianus Yasumatsu

Figures

Figures 5 - 10. Discoelius emeishanensus Zhou and Li, sp. n. 5 general habitus (lateral view), ♀ 6 frons and clypeus, ♀ 7 frons and clypeus, ♂ 8 metasomal segment 1 (lateral view), ♀ 9 antenna (lateral view), ♂ 10 metasomal segments 2 - 6 (lateral view), ♀. Scale bar: 1 mm.