Delta nigriculum Giordani Soika 1986

Nugroho, Hari, Kojima, Jun-Ichi & Ubaidillah, Rosichon, 2013, Review of potter wasps with a petiolate metasoma excluding so-called " Zethinae " (Hymenoptera: Vespidae: Eumeninae) in the Lesser Sunda Islands of the Indonesian Archipelago, Zootaxa 3608 (1), pp. 1-25 : 11-13

Delta nigriculum Giordani Soika 1986 , stat. nov.

(Figs 17, 19, 21, 23, 25, 27, 29)

Delta campaniforme nigriculum Giordani Soika 1986: 77 , Ƥ, holotype "Sumba: Mellolo [9°54'S 120°40'E]", [Museo Civico di Storia Naturale, Venice].

Delta campaniforme rendalloide Giordani Soika 1993: 162 , Ƥ, holotype "Sumba: Laluku [10°09'S 120°30'E]", [Nationaal Naturhistorisch Museum - Naturalis, Leiden]. New synonymy.

Material examined. LOMBOK I.: 1 Ƥ (MZB), 08°29'S 116°40' E, Labuhan Lombor, Lombor, Pringgabaya, J. Kojima, 8 Nov.2000. SUMBAWA I.: 1 Ƥ (MZB), 08°32'S 118°18'E, alt. 100-150 m, Banggo, Manggalawa, Dompu, J. Kojima, 13 Nov.2000; 2 Ƥ (MZB), 08°30'S 118°33'E, Tolonggeru, Bolo, Bima, J. Kojima, 11 Nov.2000; 1 Ƥ (MZB), 08°37'33.3"S 117°10'42.6"E, alt. 916 m, Tepal, Batu Lanteh, Sumbawa, H. Nugroho & Y.R. Suhardjono, 14 Apr.2010; 1 Ƥ (MZB), 08°54'53.5"S 116°44'34.8"E, alt. 34 m, Pasir Putih, Maluk, Sumbawa Barat, H. Nugroho & C. Rahmadi, 10 Apr.2010. FLORES I.: 1 Ƥ (MZB), 08°51'S 121°41'E, Nanganesa, Ndona, Ende, J. Kojima, 21 Jan.2003; 1 3 (MZB), 08°29'32.9"S 119°52'52.6"E, alt. 21 m, Labuan Bajo, E. Cholik, 2 Nov.2010. SUMBA I.: 2 Ƥ (MZB), Laiwanggi, alt. 320 m, A. Perrard, 15–19 Jun.2010. RINCA I.: 1 Ƥ (MZB), Rinca Island, alt. 18m, E. Cholik, 3–7 Nov.2010.

Redescription. FEMALE. Body length 16–20 mm; fore wing length 13–14 mm. Head in frontal view subcircular, 1.25 × as long as wide. Clypeus (Fig. 19) similar to that of D. campaniforme (Fig. 20), in frontal view as high as wide; dorsal margin emarginate medially (Fig. 19); ventral margin slightly emarginate or nearly straight. Labrum broadly rounded apically. Mandible with dorsalmost tooth long and sharp; second to fourth teeth blunt. Antennal scape 4.4 × as long as its maximum width; flagellomere 1 longer than wide, 1.5–1.8 × as long as its maximum wide.

Mesosoma globular, in lateral view 1.25 × as long as high. Pronotal carina weakly produced anteriorly at humeral angle, moderately produced dorsally. Mesoscutum 1.2 × longer than wide. Tegula convex, pointed posteriorly. Scutellum and metanotum moderately convex. Propodeum in lateral view weakly convex; posterior face barely depressed medially in dorsal half, more or less distinctly depressed medially in ventral half; apical lamella rounded.

First metasomal segment long and slender, 1.1 × longer than length of mesosoma; metasomal tergum 1 in dorsal view (Fig. 23) nearly parallel-sided in basal half, swollen at spiracles, then narrowed behind spiracles and again slightly widened posteriorly, with apical width 2.4 × the basal width of the segment. Metasomal segment 2 in lateral view (Fig. 17) slenderer than in D. campaniforme (Fig. 18); sternum 2 in lateral view with ventral margin slightly concave basally, then weakly convex apically.

Fore wing with pterostigma 1.25 × longer than prestigma.

Body covered with silvery hairs. Vertex, frons and ocular sinus strongly punctured; hairs on vertex and frons longer than those in other parts of head. Clypeus with very sparse and superficial punctures, covered with silky pubescence. Punctures on mesosoma larger and deeper than those on head, but lateral faces of propodeum with sparse and shallow punctures; pronotum, mesoscutum and mesepisternum with hairs shorter than those on head; hairs on metanotum and propodeum as long as those on the head. Metasoma with only sparse and superficial punctures as on clypeus; covered with silky pubescence.

Head and mesosoma black, with following yellow markings: band along lower part of ocular sinus reaching dorsal margin of clypeus, supraclypeal area, clypeus except narrow black band along margin of apical free part (sometimes with central reddish-brown stain), labrum (often ferruginous), narrow long band on gena along posterior margin of eye, short medio-dorsal band on pronotum (sometimes absent), band along outer margin of axillary fossa, band on metanotum, apical tip of propodeum (sometimes absent); mandibles ferruginous except its black base; antenna reddish-brown or pale-ferruginous (specimens from Sumbawa with scape dorsally having dark brown band); pronotum except black posterior margin, paired subquadrate spots on mesepisternum, scutellum except black anterior and posterior margins, metanotum except black anterior margin, paired wide lateral bands on propodeum, reddish-brown (occasionally yellow); posterior tip or posterior half of outer margin of tegula, yellow to ferruginous. Metasoma black, with following markings: metasomal segment 1 except black base, ferruginous; irregular-shaped apical spot on tergum 1, yellow; basal one third to half of metasomal tergum 2, basal two thirds of sternum 2, apical band on metasomal segments 3–6 (sometimes absent in terga 3–4), ferruginous. Coxae and trochanters dark brown to black; mid and hind coxae with longitudinal reddish-brown band; femora, tibiae and tarsi ferruginous, but fore femur and tibia with apical yellow spot. Wings fusco-hyaline, slightly darker basally.

MALE. Body length 17 mm; fore wing length 13 mm. Clypeus in frontal view proportionally narrower than in female, 1.2 × as high as wide (Fig. 21; proportionally wider than in D. campaniforme , Fig. 22). Apical part of flagellum hooked, with rounded apex of terminal flagellomere reaching the base of flagellomere 8 (Fig. 25; apex of terminal flagellomere more or less pointed in D. campaniforme , Fig. 26). Genitalia: Aedeagus (Fig. 27) slightly thicker than that of D. campaniforme (Fig. 28); digitus of volsella short, thick, with bluntly rounded apex, gradually narrowed apically (Fig. 29; abruptly narrowed in D. campaniforme , Fig. 30), covered with long hairs (Fig. 29); base of volsella with short and dense pubescences.

Color and marking pattern as in female, but: yellow markings on head more extensive; antennal scape reddishbrown dorsally, dark yellow ventrally; antennal flagellomeres 1–3 reddish-brown; flagellomeres 4–6 reddishbrown ventrally, dark brown dorsally; flagellomeres 7–10 dark brown; apex of the antenna yellow, with dark brown tip; labrum yellow; mid and hind tarsi dark brown; metasomal terga 2–7 with apical yellow band (absent in the male from Flores).

Distribution. Indonesia: *Lombok, *Sumbawa, Flores, *Rinca I., Sumba.

Remarks. Giordani Soika (1986) described D. c. nigriculum based on a single female (holotype) and a male from East Sumba. Later he (Giordani Soika 1993) described another subspecies, D. c. rendalloide , from a single female also from East Sumba, based on slight differences in color pattern from D. c. nigriculum . The specimens we examined include those that show color patterns intergrading between D. c. nigriculum and D. c. rendalloide , suggesting that D. c. rendalloide should be synonymized under D. nigriculum . The sympatric occurrences and differences not only in color patterns but also in morphological characters have revealed that D. nigriculum and D. campaniforme are distinct species.