Bembecinus pusillus (Handlirsch 1892)

Bembecinus pusillus (Handlirsch)

Stizus pusillus Handlirsch, 1892:46 [ from Andaman Islands, from Malacca and Java]; 1895:978, 1035 [lists , from Burma, Borneo, and Sumatra].—Bingham, 1897:283 [description condensed from Handlirsch, 1892].—Dalla Torre, 1897:529 [listed].

? Stizus prismaticus (Smith).—Bingham, 1896:444 [Pundaluoya; probably a misidentification of B. pusillus].

Bembecinus pusillus (Handlirsch).—Vecht, 1949:306 [brief note].—Bohart and Menke, 1976:532 [listed, Indonesia].

Handlirsch noted in his original description that he was describing this species from a male from Andaman Islands and a female from Malacca, both in the Vienna Museum, and a female from Java in the Budapest Museum. I have examined all three specimens and find that each belongs to a different species. I have selected the male as lectotype. It bears the locality label “Tlason./Anda/manen/Post II, 1878” and an identification, “pusillus/det. Handlirsch.” It agrees in the color pattern, ivory maculations, and genitalia with the Ceylonese males described below. The female from Java is a specimen of B. reversus (Smith), and the female from Malacca is apparently an undescribed species.

Bembecinus pusillus and the following species, B. proximus (Handlirsch), are distinguished from the other Ceylonese species of the genus in lacking a notch or emargination on the compressed posterolateral margin of the propodeum (cf. Figures 1, 6). The Ceylonese populations of the two species are easily separated because both sexes of B. pusillus have white to ivory maculations on the abdomen rather than bright yellow. Both species have a pair of pale spots on the first abdominal tergum, and the second and fourth have pale apical bands, but the third tergum has a median pale spot in B. pusillus and is all black in B. proximus. Furthermore, in the female of B. pusillus the antennal socket is equidistant from the inner eye margin and the base of the clypeus, whereas in B. proximus it is closer to the base of the clypeus than to the inner eye margin.

Bembecinus pusillus and B. proximus share the distinction of being the most widely distributed species of Bembecinus within Sri Lanka, although B. pusillus is somewhat less common than B. proximus. The present species occurs in both the Dry Zone and the Wet Zone from sea level to about 2200 m and with average annual rainfall ranging from 965 to 3900 mm. I have seen the species also from South India, Orissa, Deesa, Nepal, and the Andaman Islands.

The Ceylonese population has white to ivory maculations but the pale maculations of Indian specimens range from white to ivory to yellow.

FEMALE.—Length 6.3–7.6 mm. Black, the following white to ivory: palpi, labrum except a median basal spot of variable extent, clypeus rarely, part of supraclypeal area rarely, narrow short line along inner eye margin from upper margin of antennal socket halfway to anterior ocellus, antenna beneath, narrow apical margin of pronotum and lobe, narrow band on posterior two-thirds of lateral margin of scutum, spot on lateral fourth of scutellum, band on median half of postscutellum, narrow band on posterolateral margin of propodeum, apices narrowly of coxae, band beneath on fore- and midfemora, basal half of outer surface of tibiae, anterior half or more of fore tarsal segments, a pair of broad subapical spots on first abdominal tergum sometimes joined on midline, apical bands on second and fourth terga with broadly and shallowly biemarginate anterior margins, band on second wider, small median triangular spot on third tergum at apex, small round lateral spot on fifth tergum, and posterolateral triangular spots on second to fourth sterna decreasing in size posteriorly. Wings clear, veins brown.

Ocular index 1.9–2.1; distance between margin of antennal scrobe and inner eye margin subequal to that between scrobe and base of clypeus; ocellar area without median groove behind anterior ocellus.

Second submarginal cell strongly narrowed above, triangular or almost so, but not petiolate.

Median triangular area of propodeal dorsum narrowly impunctate anteriorly except at sides, elsewhere with small punctures ranging from subcontiguous to separated by half the diameter of a puncture; posterolateral angle of propodeum rounded, not notched.

Tergum VI without narrow impunctate median space but extreme apex impunctate; sterna II and III with sparser and larger punctures than in B. comberi (cf. Figure 27).

MALE.—Length 5.8–7.5 mm. Color as in female except as follows: most or all of clypeus and supraclypeal area, stripe along inner eye margin occasionally extending downward to base of clypeus, lateral stripe on scutum variable in extent but never reaching base, usually all tibiae externally, spots on tergum V sometimes extended toward middle to form a band, spots on sternum II rarely united by a narrow apical band, and sternum V usually with small, posterolateral, triangular spot.

Ocular index 2.3–2.4; distance between antennal scrobe and base of clypeus 1.7–2.0 times distance between scrobe and inner eye margin.

Second submarginal cell and propodeum as in female.

Apical margin of sternum VI broadly and shallowly emarginate; sternum VII without a median ridge; ventral aspect of genitalia (Figure 19), outer margin of paramere narrowed at middle, its apex more narrowly rounded than in B. proximus, cuspis shorter than in B. knighti.

SPECIMENS EXAMINED (all USNM except where noted).—NORTHERN PROVINCE. Vavuniya District: 1, Parayanalankulam, irrigation canal, 25 mi (40 km) NW Medawachchiya, 100 ft (30 m), 20–25 Mar, Davis et al. Mannar District: 1, 0.5 mi (0.8 km) NW Kokmotte Bungalow, Wilpattu National Park, 21–25 May, Krombein et al.; 1, Olaithoduvai, 15 ft (4.6 m), 10 mi (16.2 km) NW Mannar, 5 Nov, in Malaise trap, Hevel et al.; 6, 1, Pesalai Beach, 19 Feb, Krombein, et al.

NORTH CENTRAL PROVINCE. Anuradhapura District: 1, Padaviya, Irrigation Bungalow, 180 ft (55 m), 18 May, in Malaise trap, Krombein et al.; 1, Wildlife Society Bungalow, Hunuiwilagama near Wilpattu National Park, 200 ft (61 m), 10–19 Mar, Davis et al., 3, Panikka Wila Bungalow, Wilpattu National Park, 1 Nov, Krombein et al. Polonnaruwa District: 2, 1, Pimburettawa, 13 mi (21 km) S Mannampitiya, 1850 ft (564 m), 9–12 Nov, Flint et al.

EASTERN PROVINCE. Trincomalee District: 8, 1, Trincomalee, China Bay Ridge Bungalow, 0–100 ft (0–30 m), 27–31 Jan (5), 26 Feb (), 13–17 May (), 8–11 Nov (, ), Krombein et al.; 1, Nilaveli, 18 and 19 Nov, Kosztarab et al. Batticaloa District: 3, Madura Oya, Punani, 500 ft (152 m), 9–14 Jun, P.B. Karunaratne (Ottawa). Amparai District: 3, Panama, Radella Tank, 50 ft (15 m), 14 Jun, Krombein et al.

CENTRAL PROVINCE. Kandy District: 2, 3, Kandy, Udawattakele Sanctuary, 2100 ft (640 m), 16–31 Aug (2), 1–17 Sep (), 1–3 Oct at black light (), 27 and 28 Oct (), S. Karunaratne, Krombein et al. Nuwara Eliya District: 1, Hakgala Natural Reserve, 6 and 7 Feb, Krombein et al.

WESTERN PROVINCE. Colombo District: 12, 2 , Colombo (includes Colpetty (103 Galle Road), Victoria Park, Colombo National Museum), 7 (2), 8 () and 16 (4) Apr, 15 (2) May, 8 () Jul, 25 () and 26 () Aug, 21 () and 23 () Nov, Halstead, Wijesinhe (USNM, San Francisco); 4, Nugegoda, Papiliyana, 3 and 4 May (3; 5375 A, 5475 A, B), 5 Jul (; 7575 A), P.B. Karunaratne; 2, Gampaha Botanic Garden, 4 Mar, 24 May, Krombein et al., Messersmith et al.; 6, 1, Labugama Reservoir, 400 ft (122 m), 9 May (6), 11 Jul (), Krombein et al.; 4, 8, Ratmalana near airport, 50 ft (15 m), 13 Jan (), 6 June (4, 7); 1, Padukka, Arakawila Jungle, 10 Dec, P.B. Karunaratne.

SABARAGAMUWA PROVINCE. Kegalla District: 1, 4, Kitulgala, Makande Mukalana, 3 and 4 Feb, Krombein et al. Ratnapura District: 9, 4 Gilimale, Induruwa Jungle, 2 Feb (), 5–7 Feb (), 7 and 8 Mar ( in Malaise trap), 16–19 Apr (2, 1 in Malaise trap), 17–21 Jun (5, 2; 1 in Malaise trap; 3, 61776 B–D), 10 Oct ( in Malaise trap), Krombein et al. 2, Rajawaka, 20 Jun, Krombein et al.; 1, Panamure, 500 ft (152 m), 15–21 Oct, Flint et al.; 1, Pubbarapotha, Katupat Oya, 400 ft (122 m), 14 Oct, Flint et al.; 2, Uggalkaltota, 31 Jan–5 Feb, 23–26 Jun, Davis et al., Krombein et al.

UVA PROVINCE. Badulla District: 1, Ulhitiya Oya, 15 mi (24 km) NNE Mahiyangana, 5 and 6 Sep, Krombein et al. Monaragala District: 18, 9, Angunakolapelessa, 100 m, 21–23 Jan (4, 4 in Malaise trap), 27 and 28 Mar (2, 1; 1, 1 in Malaise trap), 17–19 Jun (12, 4; 2, 2 in Malaise trap), Krombein et al.; 1, 1, Mau Aru, 10 mi (16.2 km) E Uda Walawe, 100 m, Krombein et al.; 1, Nilgala, 1–14 Jul, P.B. Karunaratne (Ottawa); 1, Inginiyagala, 3 Sep, Keiser (Basel).

SOUTHERN PROVINCE. Hambantota District: 1, 1, Palatupana, WLNPS Bungalow, 0–50 ft (0–15 m), 18–21 Jan (), 2–6 Feb (), Krombein et al.

Bembecinus pusillus (Handlirsch)

P.B. Karunaratne made notes in 1975 on four nests (5375 A–C and 7575 A) in a pile of sand accumulated for building purposes at Papiliyana, Nugegoda, near Colombo. I found five nests in 1976 (61776 C, D, and 61976 A–C) at Gilimale, Induruwa Jungle, and captured two wasps flying with prey (61776 B and 61976 D) at the same locality.

Karunaratne observed 5375 A enter her nest with prey at 1345. The wasp emerged head first in a few minutes and began to kick sand backward to close the entrance. She was captured when this was completed. The burrow was 4 mm in diameter and went in at an angle of 30° to the horizontal. The temporary closure at the entrance was about 13 mm long and the burrow was empty for the next 38 mm. Karunaratne found six cicadellid prey, 4.5–6.0 mm long, placed horizontally at the end of the burrow with no indication of a cell, and no wasp egg or larva. The prey were identified as one adult Platytretus marginatus M