Description:
Female: Head width is three times greater than its length, and wider than the thorax. The vertex behind the ocelli does not abruptly bend and lacks a transverse ridge. The posterior ocelli are positioned near the compound eye margin, with the distance between them being less than the diameter of the ocellus. The postocular area is very narrow, its width being less than 1/4 of the compound eye width. The frons is not concave in the middle, lacks transverse striations, and does not bulge between the antennal socket and the compound eye margin. Most of the frons is smooth and shiny. The compound eyes are oval, with a length greater than the width (14:10), and the distance between the two compound eyes is greater than the width of an individual eye. At 56x magnification, short hairs are clearly visible on the compound eyes. The gena (cheek) is shorter than the length of the compound eye. The vertex and gena have small granular sculpture, with the sculpture on the gena being slightly less distinct than on the vertex. The antennae have 11 segments and are clavate (club-shaped). The scape (first antennal segment) is six times longer than its width, approximately five times longer than the radicle, and four times longer than the second antennal segment. The second antennal segment is longer than the third. The fourth antennal segment is longer than the fifth, but shorter than the third. Segments five and six are small, with segment six wider than it is long. The antennal club consists of 5 segments, and the total length of the club segments is 3.5 times greater than their maximum width and less than the length of the scape.
The thorax is slightly longer than wide. The mesoscutum (middle dorsal plate of the thorax) lacks a longitudinal groove and has small granular sculpture similar to that on the vertex. The scutellum is almost smooth and shiny. The forewing length is approximately 2.7 times greater than the width, the postmarginal vein is 1.5 times longer than the stigmal vein, and the second recurrent vein is twice as long as the marginal vein.
The abdomen is narrower than the thorax, and its length is 1.2 times greater than its width. The first tergite (dorsal plate) is 2.5 times wider than it is long, and its length is equal to 1/3 of the length of the second tergite. The second tergite is wider than it is long (20:18) and occupies the majority of the abdominal length. The remaining tergites are very small. The ovipositor is not exposed. The first tergite and the base of the second tergite have short longitudinal striations; the remaining part of the second tergite is smooth and shiny.
The body is black. The antennae are black, the wings are almost transparent, and the wing veins are brown. The legs are yellow.
The male resembles the female in shape and color. It differs from the female by having 12-segmented antennae that are filiform (thread-like).
Size:
Body length is approximately 0.7 mm.
Ecology:
From the eggs of the cabbage white butterfly (Pieris sp.), a pest of vegetables.
Distribution:
Vietnam: Son La, Hanoi, Hai Phong.
Type Material:
1 female (holotype), 2 females and 2 males (paratypes), Hanoi (Gia Lam), 30/11/1978; 1 female (paratype), Son La, 2/5/1986 (V. Triapitxun), 1 female (paratype), Nam Hai Phong, 20/5/1986 (A. Sarkov).