Serendibula karunaratnei Krombein 1983

Serendibula karunaratnei

This species occurs in the hill country of the Wet Zone in areas having a moderate annual rainfall averaging 1950 mm. It is particularly common along the highest ridge in Udawattakele Sanctuary, Kandy, where we collected 60 females and 15 males in or on leaf litter during March, April, July, September, and October. Presumably it is active in Kandy during much of the year except possibly during the two driest months, January and February.

Females of S. karunaratnei are similar in appearance to those of S. deraniyagalai Krombein, a species of the Dry Zone in the southeastern part of Sri Lanka. The female has close longitudinal carinae on the second metasomal tergum only, but they cover a more extensive area than in S. deraniyagalai, being present on the basal fourth or third of the length along the midline rather than the basal eighth or sixth, and on more than half the surface laterally instead of less than half. The female of S. karunaratnei is similar in the extent of this basal carinate area to females of S. insolita, new species, and S. gracilis, new species, but has a relatively broader abdomen (first metasomal tergum 0.58–0.60 times as long as broad, see Figure 64) rather than the narrower abdomen (first metasomal tergum 0.64–0.73 times as long as broad) of those two species (Figures 62, 63).

Males of S. karunaratnei are also quite similar in appearance to those of S. deraniyagalai. Both species have some of the pronotal punctures arranged contiguously in oblique or arcuate rows, but lack transverse rows of contiguous punctures on the scutum as in S. kasyapai, new species. The appendages are predominantly dark in S. karunaratnei, whereas the scape is entirely light red in S. deraniyagalai and the fore and mid-tibiae are predominantly so. The metasoma is relatively broader in S. karunaratnei, the apical width of first being 2.85 times the length, whereas in S. insolita the width of the first is only 2.49 times the length.

ETYMOLOGY.—I take pleasure in naming this species for P.B. Karunaratne, former Curator of Insects in the Colombo Museum, companion on most of my collecting trips in his country, and collector of many of the specimens on which this contribution is based.

HOLOTYPE.— Sri Lanka, Central Province, Kandy District, Kandy, Udawattakele Sanctuary, 600 m, on or in leaf litter, 12–14 Oct 1980, K.V. Krombein, P.B. Karunaratne, T. Wijesinhe, L. Jayawickrema, V. Gunawardane (USNM Type 100447).

FEMALE.—Length 4.5 mm. Black and shining, top of head and dorsum of thorax dull from close punctation; mandible, lower half of malar space and thorax ferruginous; first flagellar segment amber; coxae in part and trochanters stramineous. Erect vestiture moderately long, black except cinereous on eye, mixed black and cinereous on femora and tibiae, and whitish on metasomal sterna and edges of terga.

Head as in S. deraniyagalai.

Thorax as in S. deraniyagalai except median length of pronotal dorsum 1.9 times combined lengths of scutum and scutellum; combined lengths of latter two sclerites 0.9 times the length of postscutellum; enclosed triangular area of postscutellum 1.4 times as long as basal width.

Abdomen as in S. deraniyagalai except punctures on first two terga tiny and scattered; close longitudinal carinae on second tergum a fourth as long as tergum on midline and 0.6 times as long as lateral length (Figure 64).

ALLOTYPE.— same locality as holotype, but 18–20 Mar 1981, on leaf litter, K.V. Krombein, T. Wijesinhe, L. Weeratunge (USNM).

MALE.—Length 4.0 mm. Black, dorsum of head and thorax dull from coarse punctation but the interspaces between punctures glossy; apical half of mandible and scape beneath dark red; fore tibia brown, paler beneath as is the declivous surface of first metasomal tergum. Vestiture shorter than in female, whitish to cinereous except dark on flagellum. Wings clear, costa and stigma black, other veins medium brown.

Head as in S. deraniyagalai except: width 1.1 times height from clypeal apex to posterior ocelli; frontal concavity with weak median ridge; interocular distance at anterior ocellus 0.5 times head width.

Thorax as in S. deraniyagalai except: pronotum and scutum subequal in length; scutum subequal in length to scutellum and postscutellum combined, the latter two sclerites also subequal in length; U-shaped enclosed area of postscutellum 1.1 times as long as basal width.

Abdomen as in S. deraniyagalai except digitus as long as aedeagus in a paratype.

PARATYPES.—68, 18, as follows (all USNM). 2, 5, same label data as allotype; 4, same label data as allotype but 22 Mar 1981; 4, 4, same label data as allotype but 25–27 Apr 1981; 1, same locality but 2100 ft (628 m), 13 Jul 1976, S. Karunaratne; 6, same locality but 1800 ft (547 m), 21–22 Sep 1980, in or on leaf litter, K.V. Krombein, P.B. Karunaratne, T. Wijesinhe, L. Jayawickrema, V. Gunawardane; 6, same label data as preceding but 23–25 Sep 1980; 41, same label data as holotype. CENTRAL PROVINCE. Kandy District: 2, Thawalamtenne, in Malaise trap, 7–8 Sep 1980, K.V. Krombein, P.B. Karunaratne, T. Wijesinhe, L. Jayawickrema, V. Gunawardane. SABARAGAMUWA PROVINCE. Kegalla District: 9, 2, Kitulgala, Bandarakele, in or on leaf litter, 15 Apr 1981, K.V. Krombein, L. Weeratunge, P. Leanage. Paratypes of both sexes will be placed in the Colombo and British museums. Three females from Kandy, May 1917, O.S. Wickwar (Colombo Museum) are excluded from the type series because they are moldy and broken.

Female paratypes are 4.0–5.2 mm long and may vary from the holotype in certain details: malar space may be red only above mandibular articulation; antenna may be entirely black; coxae may be black to a greater extent; median pronotal length is 1.9–2.2 times as long as combined lengths of scutum and scutellum; latter two sclerites are 0.8–0.9 times as long as postscutellum; postscutellar length is 0.6–0.8 times basal width of enclosed area; first metasomal tergum may have small rather than tiny punctures and the carinate area of second tergum is 0.2–0.3 times length of tergum along midline and 0.5–0.7 times as long as lateral length.

Male paratypes are 3.7–5.1 mm long and may vary from the allotype as follows: scape beneath and declivous surface of first metasomal tergum are rarely lighter red; mid-tibia is rarely light brown beneath toward apex; head width is 1.1–1.2 times height from apex of clypeus to posterior ocelli; frontal concavity may have median ridge evanescent or absent; interocular distance at anterior ocellus is 0.4–0.6 times head width; pronotal length is 0.9–1.0 times length of scutum; scutum is 1.0–1.3 times combined lengths of scutellum and postscutellum; scutellum is 1.0–1.2 times as long as postscutellum; and length of U-shaped area of postscutellum is 1.1–1.2 times basal width.