Loboscelidia atra Krombein 1983

Loboscelidia atra

Loboscelidia atra is distinguished immediately by its intense black integument, other known species ranging from dark brown, chestnut, and lighter shades of brown to light red. Structurally it is most similar to the Bornean L. maculipennis Fouts and the Philippine L. philippinensis Fouts in having incomplete notauli which do not reach the posterior margin of the scutum, and in having an elongated vertex. Loboscelidia maculipennis has stout clavate setae on the cheeks and fine close arcuate carinae on the upper front, whereas L. atra has only fine setae on the cheeks and delicately alutaceous upper front. In L. philippinensis the submarginal frontal ridge is evanescent at the upper eye margin and does not attain the occiput and the anterior part of the pronotum is concave from side to side, whereas the submarginal frontal ridge is well developed for the entire length in L. atra and reaches the occiput, and the anterior part of the pronotum is convex from side to side.

Loboscelidia nigra Fouts is misnamed. The holotype and single paratype from the Philippines are castaneous, not black. The species also differs from L. atra in having complete notauli that reach the posterior margin of the scutum and in having a very reduced inconspicuous lamina on the scape.

Loboscelidia atra is known only from the unique male holotype from the lowland rain forest of Sinharaja Jungle. Inasmuch as sexual dimorphism is not at all well developed in this subfamily, the female of L. atra should be readily recognized by its probable black color, presence of an ovipositor, short stout antenna in which the sixth through tenth flagellar segments are broader than long, and the basal segments about as broad as long.

HOLOTYPE.—; Sri Lanka, Sabaragamuwa Province, Ratnapura District, Sinharaja Jungle, Waturawa Forest, 3 km S of Kudawe, on low foliage 4–10 in (10.2–25.4 cm) above ground, 2 Jul 1981, P.B. Karunaratne (USNM Type 100458).

MALE.—Length 3.1 mm, 5.1 mm to apex of fore wing. Intense black, entirely glossy except upper front and cheeks, and lower tegula somewhat dull. Vestiture white, very sparse on body, denser on legs especially on tarsi beneath. Wings very lightly infumated and with darker infuscated areas, veins testaceous at base, brown across middle (Figure 33).

Head much narrower than thorax (0.65 times its width) at tegulae and 1.7 times least interocular distance; clypeus with two delicate transverse carinules, its upper margin delimited by an arcuate ridge, lateral ridge lacking; process below antennae two-tiered, the lower plate narrower and with gently emarginate apex, the upper plate broader, deeply emarginate between rounded lateral lobes; upper horizontal front delicately alutaceous, with a strong lateral ridge near inner eye margin extending to occiput (Figure 34b); vertex shallowly impressed behind ocelli, strongly arched in profile, 1.6 times as long as wide, sides subparallel; vertex and side of cheek margined by a fimbria of long flattened, close-set, curved transparent setae whose edges overlap slightly so that the fimbria has a ribbed appearance (Figures 34a,c); ocelli in a low triangle, postocellar and ocellocular distances subequal; antenna very elongate, filiform, 1.5 times as long as body, scape with a complete, narrow transparent lamina on lower margin, scape 1.3 times as long as pedicel and first flagellar segment combined, first through tenth flagellar segments subequal in length, 2.3–2.5 times as long as broad, last flagellar segment 1.3 times as long as preceding segment; flagellar segments subcircular in cross-section, clothed with numerous short, appressed sensory setae, many lying in elongate pits.

Thorax (Figures 36, 37) entirely glossy except lateral area of tegula very delicately alutaceous, pronotum, scutum, mesopleuron and propodeum with extremely scattered micropunctures each bearing a short decumbent seta; anterior two-thirds of pronotal disk convex, posterior third with a shallow oblique impression from near posterolateral angle toward midline, anterior width 0.76 times posterior width and 0.85 times length; anterior margin of lateral pronotal surface with a fringe of dense, short, straight flattened setae on upper half; tegula enormous, in dorsal view 2.4 times as long as greatest width, lower area very delicately alutaceous, surface with a few scattered decumbent setae; scutum with notauli straight, diverging anteriorly, extending five-sixths of the distance to apex; axilla not foveate; scutellum anteriorly with somewhat larger, closer punctures and posteriorly with longitudinal arcuate ridges and subcontiguous punctures; postscutellum with a small median triangular roughened area; fore wing (Figure 33) lacking costa and stigma, basal vein complete; fore and mid-femur with transparent lamina on apical half of lower edge, narrow at base, rounded and broader toward apex; hind femur with a similarly placed lamina which extends four-fifths toward base (Figure 35); fore and mid-tibiae with a transparent narrower lamina on basal half of lower edge; hind tibia with a broader lamina extending three-fourths toward apex (Figure 35); tarsal claws with a small erect subbasal tooth.

Metasoma glossy, the four exposed segments impunctate except for a narrow area of close tiny punctures at base of third tergum.

FEMALE.—Unknown.