Loboscelidia castanea Krombein 1983

Loboscelidia castanea

Loboscelidia castanea is easily distinguished from L. atra by its smaller size, chestnut color, complete notauli on the scutum, concave surface of axilla, and the rugulosoreticulate posterior half of the scutellum.

The species is known from only two males from the lowland rain forest of the Sinharaja Jungle collected in exactly the same type locality as L. atra. The unknown female will probably be very similar to the male of L. castanea in size and color.

HOLOTYPE.—; Sri Lanka, Sabaragamuwa Province, Ratnapura District, Sinharaja Jungle, Waturawa Forest, 3 km S of Kudawe, on foliage near ground, 7 Oct 1981, P.B. Karunaratne (USNM Type 100459).

MALE.—Length 1.9 mm, 3.1 mm to fore wing apex. Castaneous, the abdomen somewhat lighter, entirely glossy except lower edge of tegula. Vestiture white, very sparse on body, denser on legs. Wings very lightly infumated and with darker infuscated areas, veins testaceous at base, brown across middle.

Head narrower (0.76 times) than thorax at tegulae and 1.6 times least interocular distance; clypeus with one delicate transverse carinule, its upper margin delimited by an arcuate ridge, lateral ridge lacking; process below antenna two-tiered, lower plate narrower and with truncate apex, the upper plate broader, deeply emarginate between subtruncate lateral lobes; upper horizontal front more delicately alutaceous than in L. atra, with a weaker lateral ridge near inner eye margin extending to occiput; vertex shallowly impressed behind ocelli, strongly arched in profile, 1.9 times as long as median width, sides arched inwardly; vertex and side of cheek with a curved fimbria of flattened setae as in L. atra; ocelli in a low triangle, the postocellar distance 0.8 times ocellocular distance; antenna 1.5 times as long as body, scape with a complete, narrow transparent lamina on lower margin, scape 1.6 times as long as pedicel and first flagellar segment combined, first through tenth flagellar segments subequal in length, 2.1–2.3 times as long as broad, last flagellar segment 1.5 times as long as penultimate; flagellar segments subcircular in cross-section, clothed with numerous short, subappressed and appressed sensory setae, the latter lying in elongate pits.

Thorax entirely glossy except narrow lower margin of tegula delicately alutaceous, pronotum, scutum, mesopleuron, and propodeum with extremely scattered micropunctures, each bearing a short decumbent seta; pronotal disk evenly convex except posterolateral area with a small depression, anterior width 0.69 times posterior width and 0.89 times length; anterior margin of lateral pronotal surface with a fringe of dense, short, flattened setae on upper half; tegula enormous, in dorsal view 2.3 times as long as greatest width, surface with a few scattered decumbent setae; scutum with notauli straight, diverging anteriorly, complete posteriorly; axilla concave; scutellum anteriorly with a few larger punctures, posterior half rugulosoreticulate; postscutellum with a small median roughened triangular area bearing a short median keel; fore wing as in L. atra (Figure 33); 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; 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; tarsal claws with a small erect subbasal tooth.

Abdomen glossy, impunctate.

FEMALE.—Unknown.

PARATYPE.—1, same label data as holotype (USNM). The paratype is very similar to the holotype in all details except that it is larger, comparable lengths being 1.9 and 3.3 mm, and the third metasomal tergum has several larger scattered punctures across midline. It will be deposited in the Colombo Museum.