Isoneuromyia splendida Evenhuis, n. sp.

(Figs. 1, 4, 7, 17, 20, 31, 34)

Diagnosis

Closest to brunettii but can be distinguished from it by the brown basal antennal flagellomeres (these basal segments yellowish orange in brunettii).

Description

MALE. Lengths: Body: 15.0– 18.5 mm; wing; 8.0–10.0 mm.

Head. Vertex and occiput immediately behind ocelli black; remainder of occiput orange with fairly dense small black recumbent hairs. Ocelli in horizontal line. Frons black, bare. Antennae: scape and pedicel black basally, brown apically. Flagellum: segments slightly compressed; flagellomeres 1–7 brown; flagellomeres 8–14 yellowish. Face orange, yellowish pruinose with small black hairs apicolaterally. Palpi dark brown. Proboscis orange.

Thorax. Mesonotum yellowish with three black stripes coalesced into one (Fig. 17), medial stripe extending anteriorly to pronotum. Scutellum dark brown. Mesonotum with uniformly distributed recumbent yellow hairs dorsally, patch of thick black setae above wing root and on posterior margin of scutellum. Prescutellar area tapering to scutellum. Pronotal lobes dark brown with dense black setae. Pleura and mediotergite dark brown, bare. Halter orange, knob orange with brown dorsally.

Legs. Fore and mid coxae orange, hind coxa brown, all with admixture of yellow tomentum and black hairs. Fore and mid femora reddish brown, hind femur black, all with recumbent black hairs. Fore tibia with orange tibial pecten apically. Tibial spurs black. Fore basitarsus 1.3 x length of fore tibia. Mid and hind basitarsi subequal in length to lengths of respective tibiae. Claws minute.

Wing (Fig. 20). Grayish yellow hyaline anteriorly along costal margin, becoming more clear posteriorly; vein R4 slightly sinuous, ending in C slightly beyond end of R1; veins M2 and CuA1 not quite reaching wing margin; vein A1 complete.

Abdomen. Tergites I–III black with orange basally, dense black recumbent hairs on black portion of segments, bare on yellow portion; tergites IV–VII predominantly yellowish orange; tergites IV, VII­VIII with yellow hairs; tergites V–VI with black tomentum, densest apically. Sternum patterned as on tergites.

Hypopygium (Fig. 34). Gonocoxites and gonostyli yellowish brown, densely fine yellow pilose, apex bidentate, basal tooth shaped like a shark’s tooth; two minute dark sclerotized teeth in between large darkly sclerotized teeth (Fig. 34 B).

FEMALE. Unknown.

Types

Holotype ♂ (BPBM 16,597) from: LAOS: Vientiane Province: Ban Van Eue, 29 Mar 1966, native collector. Paratypes: LAOS: Vientiane Province: 1♂, Ban Van Eue, 15–31 May 1965, native collector; 1♂, same data, 15 May 1966; 1?[abdomen missing], same data, 31 May 1966; 2♂, same data, 30 June 1966. Holotype in BPBM. Paratypes in BPBM and MNHN.

Etymology

The species epithet derives from the Latin splendidus = bright, shining, referring to the striking contrasting color pattern of the thorax, legs, and antennae.