Eustenogaster spinicauda Saito

Saito, Fuki & Kojima, Jun-Ichi, 2007, A taxonomic revision of the hover wasp genus Eustenogaster van der Vecht (Insecta: Hymenoptera; Vespidae, Stenogastrinae), Zootaxa 1556, pp. 1-30 : 27-28

Eustenogaster spinicauda Saito , sp. nov.

This species is similar to E. calyptodoma , but can be distinguished from the latter by the following characters: larger body size (see below); female clypeus and supraclypeal area with sparse and shallow punctures, impunctate supraclypeal area larger than in E. calyptodoma , and space between antennal sockets irregularly punctate; punctures on mesoscutum sparser, some interspaces in anterior part larger than puncture; female sixth metasomal tergum with stout spine ( Fig. 50 ); dorsal half of male clypeus more or less convex ( Fig. 51 ), ventral half of clypeus slightly concave; digitus apically with long hairs ( Fig. 59 Y); aedeagus more elongate than in E. calyptodoma ( Fig. 59 M); gena and eye emargination entirely black.

Female. Body length (head + mesosoma + first two metasomal segments) 18.5–21 mm (holotype: about 21 mm); forewing length 14.5–16 mm (holotype: about 15 mm).

Head in frontal view about as wide as high ( Fig. 52 ). Eyes in lateral view ( Fig. 53 ) with maximum width about 4.1 times as wide as that of gena. Anterior ocellus about 1.3 times larger in width than posterior ocellus ( Fig. 54 ); distance between anterior and posterior ocelli shorter than diameter of posterior ocellus; posterior ocelli separated from each other by distance about equal to or slightly larger than their diameter.

First metasomal tergum narrow and long (7.2–8.2 mm long), about 5.7 times longer than its maximum height, about 5.8 times longer than the maximum width.

Color: Body black; marking pattern and wing coloration similar to that of E. calyptodoma , but differing in spot in eye emargination absent ( Fig. 58 ) and in basal part of second metasomal tergum colored pale-brown or orange instead of yellow.

Male. Body length (head + mesosoma + first two terga) 16–18.5 mm; forewing length 14–15.5 mm. Head in frontal view about as wide as high ( Fig. 55 ); eye enlarged, in lateral view strongly swollen ( Fig. 51 ), with maximum width slightly more than five times as wide as that of gena; clypeus entirely yellow or with only small, black spot; eye emargination sometimes with small yellow spot; mandible sometimes with yellow spot at base; propodeum with dorsolateral yellow marking, sometimes split into two spots.

Type material: Holotype female (deposited in RMNH) labeled “Catbalogan, Samar, Eustenogaster spinicauda , Ψ, m. det. J.v.d.Vecht, 1960” and “ Paratype ”.

Paratypes: Philippines: 1ɗ ( RMNH), Catbalogan, Samar; 1Ψ ( RMNH), Surigao, Mindanao, JvdV; 4ɗ ( GMNH), Borongan, E. Samar, 7–18.v.1984, CKS; 2Ψ42ɗ ( GMNH), Leyte, Baybay, CKS [2Ψ30ɗ, 28.viii.1980; 3ɗ, 27–29.viii.1980; 2ɗ, 5.ix.1984; 4ɗ, 29.iv.1987; 3ɗ, 6.v.1987]; 2Ψ ( GMNH), Mindanao, Bukidonon, Musuan, Maramag, 3.i.1985, CKS & L. Pinto.

Distribution: Philippines: Mindanao, Leyte, Samar.

Etymology: The specific name spinicauda is based on van der Vecht’s manuscript name. This is a compound of a feminine Latin noun, spini (= thorn-bush), and a feminine Latin noun, cauda (= tail), referring to the stout spine of the female sixth metasomal tergum.

Figures

FIGURE 58. Facial marking pattern of Eustenogaster species.

FIGURE 59. Male genitalia in Eustenogaster species. (A) E. gibbosa, in ventral view. (B – M) aedeagus in lateral view; (N – Y) vollsela with digitus in lateral view; (B, N) E. agilis; (C, O) E. fulvipennis; (D, P) E. fraterna; (E, Q) E. scitula; (F, R) E. calyptodoma; (G, S) E. gibbosa; (H, T) E. hauxwellii; (I, U) E. micans; (J, V) E. latebricola Saito, sp. nov.; (K, W) E. palavanica; (L, X) E. luzonensis; (M, Y) E. spinicauda Saito, sp. nov..

FIGURES 50 – 56. Eustenogaster spinicauda Saito, sp. nov.; 50, 52 – 54. 56, female holotype. 55 and 51, male paratype. 50, sixth metasomal tergum in lateral view. 51 – 53. 55, head; 52 and 55, frontal view, 51 and 53, lateral view. 54, ocelli. 56, second metasomal tergum in lateral view. Scale bars show 1 mm.