Eustenogaster calyptodoma Sakagami & Yoshikawa 1968

Eustenogaster calyptodoma (Sakagami & Yoshikawa, 1968)

Stenogaster calyptodoma Sakagami and Yoshikawa, 1968: 77.

Sakagami and Yoshikawa (1968) recognized this species mainly based on its nest structure and nesting behavior, but they described the morphology of the female only briefly in comparison with E. micans, for which, however, detailed description of morphological characters is yet unavailable. Detailed description of the morphological characters for both females and males of E. calyptodoma is herewith provided based on specimens, including the holotype, from various localities.

Female. Body length (head + mesosoma + first two terga) 15.0– 16.5 mm; forewing length 11.5–12.5 mm. Clypeus slightly convex, covered with dense, fine punctures; apex sparsely hairy, with median impunctate ridge; extreme apex truncate (Fig. 21). Frons finely punctate, but area between antennal sockets with coarse punctures; two small (smaller than anterior ocellus) spots, one at the center of supraclypeal area and the other just below anterior ocellus, impunctate. Anterior ocellus, 0.26–0.30 mm wide, 0.22–0.28 mm long, about 1.4 times as wide as posterior ocellus (diameter 0.18–0.22 mm); distance between anterior and posterior ocelli shorter than diameter of posterior ocellus; posterior ocelli separated by distance about equal to or slightly larger than their diameter. Vertex with dense, long hairs. Mandible: Proximal tooth small, blunt apically; midtooth shallowly and broadly emarginate apically; distal tooth large, blunt apically (Fig. 22).

Pronotum posterolaterally with fine and dense punctures; dorsolaterally with deep furrows behind pronotal collar (Fig. 23); lateral furrow present, ending posteriorly before humeral tubercle. Scutum finely and densely punctate. Scutellum shallowly, sparsely punctate, anteriorly with short hairs, posteriorly with rather long hairs. Metanotum convex, hairy, with shallow punctures. Mesepisternum hairy, with fine, shallow punctures. Propodeum without punctures, posterodorsally covered with long hairs.

First metasomal tergum slender (6.1–6.9 mm long), about six times as long as its maximum height, about six times as long as its maximum width; second tergum in profile only weakly convex dorsally (Fig. 24); sixth tergum with prominent but small tubercle (sometimes blunt); posterior parts of second to sixth metasomal segments covered with hairs.

Color: Black; antenna dark brown, but flagellum paler beneath; apical margin of clypeus dark brown; first metasomal tergum dark reddish-brown but black posterodorsally; following parts yellow: wide band forming V-shaped marking over clypeus and supraclypeal area (Fig. 57), spot above antennal socket, small spot in eye emargination, small spot beside top of inner eye margin, variable-sized marking in ventral part of gena, broad band (interrupted medially) along posterodorsal margin of pronotum, paired spots on scutellum, anterior band of metanotum, scrobal spot and large spot below it on mesepisternum, dorsolateral longitudinal bands on propodeum, anterior band (sometimes interrupted medially) and paired lateral spots on second tergum, paired anterolateral bands or spots on third to fifth terga, paired spots on second to fifth sterna (spots on fifth reduced in size). Legs brown, with following parts yellow: fore leg: small spot on coxa, lateral side of femur, tibia and tarsus; mid-leg: apical part of tibia and basal half of first tarsomere; paired spots on hind coxa. Wings semihyaline, pale brown, darker along anterior margin of forewing; veins brown.

Male. Body length (head + mesosoma + first two terga) 13.5–16.5 mm; forewing length 11.0– 12.5 mm. Similar to female both in structure and coloration, but clypeus slightly convex only in dorsal half and with dense short hairs; clypeal apex bluntly triangular; mandible single-toothed, rounded apically, with sparse, short hairs; terminal sterna covered with hairs except for median area having sparse hairs; facial yellow markings more extensive than in the female (Fig. 57); mandible with basal yellow spot.

Genitalia: Volsella medially with sharp spine; beak-shaped digitus apically with several setae (Fig. 59 R); ventral margins of pennis valves minutely serrated in proximal part of valves.

Material examined. Thailand: 1ɗ (RMNH), Nabon [8°15’N, 99°35’E], 17.vii.1961, K. Yoshikawa; 3Ψ1ɗ (RMNH), Songkla Province, MH [2Ψ, 9.ix.1975; 1Ψ1ɗ, Buri Pat water fall, 1977]. Malaysia: Peninsular Malaysia: Selangor: 3Ψ (RMNH), Ulu Gombak, 29.vii.1957, E.F. Allen; 1Ψ (RMNH), Ulu Langat, Sungei, Chongkik, 14.i.1963, HTP; 1Ψ, (RMNH), Ulu Gombak, 16 miles from Kuala Lumpur, 1977, MH; 2Ψ (GMNH), Ulu Gombak, 24km from Kuala Lumpur, 1982, MH; Johore: 3Ψ (RMNH), Lenggor FR, 11.ii.1968, C.G. Roche; 7Ψ1ɗ (RMNH), Mt. Kluang, 500m, 5km east of Lembak, 29.vii.1972, JvdV; other: 1Ψ (RMNH), Jor Rd. milestone 23, 700m, Cameron Highlands, Perak–Pahang, 13.iii.1963, MAL; 1Ψ (RMNH), W. Kedah foot of Genun [= Mt.] Djerai, Gurun, 22.ii.1963, MAL; Borneo: Sabah: 4Ψ (GMNH), Ulu Dusun, 1977, MH; 2ɗ (GMNH), Mt. Kinabalu NP, 1977, MH; 1Ψ (GMNH), Marak, Parak, 06°19’N, 116°44’E, 26–27.v.1985, CKS; 1Ψ (RMNH), Bettotan, near Sandakan, 29.vii.1927, CBK & HMP; 1Ψ (SKYC), Tawau Hills, NP HQ, 12.vii.1996, SkY; 1Ψ (SKYC), Poring, 600m alt., 24.viii.1997, SkY; Sarawak: 1Ψ (Holotype of E. calyptodoma), Kampong Astana near Kuching, 8.ix.1966, Sakagami & Yoshikawa; 1 Ψ (SKYC), Bako NP, Forest, 21–22.iv.1993, SkY. Brunei: 1Ψ (SKYC), Tasek Merimbun, Tutong, viii.1999, K. Eguchi. Indonesia: Sumatra: South Sumatra: 1Ψ (RMNH), Gn. Betoeng, 400m, Soengeilangka Est, 27.iii.1937, JvdV; 2Ψ (RMNH), S.W. Lampung distr., Mt. Tanggamoes, Gisting ult., xii.1939, MAL; West Sumatra: 1Ψ (RMNH), Anei Kloof, 500m, 1926, E. Jacobson; 1Ψ (IUNH), 00°54.5’ S 100°28.5’ E, Campus of Andaras University, Padang, 2.xi.2001, JK; 1ɗ (RNMH), Marang, Coll. Gribodo; Kalimantan: East Kalimantan: 2ɗ (RMNH), 95m, Gunungsari, 15.viii.1956, AMRW; 1Ψ (RMNH), 75m, Kembang, Djangut, 22.xi.1956, AMRW.

Distribution: Thailand; Malaysia: Peninsular Malaysia, Sabah, Sarawak; Brunei; Indonesia: Kalimantan, Sumatra.