Onchopelma majus Evenhuis

Evenhuis, Neal L., 2002, Review of the genus Onchopelma Hesse, with descriptions of new species (Diptera: Mythicomyiidae), Zootaxa 64, pp. 1-12 : 7-9

Onchopelma majus Evenhuis , sp.n.

( Figs. 5 , 11 )

DIAGNOSIS. Most similar in appearance to brevifasciatum , sp.n. but separated from it by all yellow frons, the smaller second antennal flagellomere, the absence of lateral black spots on the abdominal tergites and the presence of complete transverse black crossbands on abdominal terga 1­7.

DESCRIPTION. Female. Length: 2.90–3.25 mm. Head ( Fig. 5 ) higher than long; eyes dichoptic, separated at vertex by 1.5 x distance between lateral ocelli; vertex black; occiput black dorsomedially, yellow dorsolaterally, laterally and ventrally, with sparse white hairs, densest laterally; frons yellow; face and tip of oral margin white; antenna with scape short, subtrapezoidal, yellow­brown; pedicel subrectangular, slightly longer than wide, yellowish; first flagellomere linear, length ca. 4 x than width, brown; second flagellomere linear­ovate, one­half length of first flagellomere, brown with small transparent apical style; proboscis brown, two­thirds head length; labrum sclerotized, stiff, pointed apically; palpus not evident.

Thorax. Mesonotum white with black patterning as in Fig. 5 , short sparse white hairs on humeral and prescutellar areas; pronotum black; scutellum yellow, black at extreme base, with sparse white hairs; pleura white except for black on katepisternum, meron; mediotergite yellow, black only beneath scutellum; coxae and legs white; halter stem and knob white.

Wing. Hyaline; veins pale yellowish; costa ends slightly beyond end of R4+5; vein Sc incomplete; crossvein dm­cu closing cell dm absent; CuA1 closing anal cell before wing margin leaving stalk; stalk length slightly less than crossvein bm­cu; fringe of hair on posterior margin of wing in alular lobe and anal lobe areas sparse.

Abdomen ( Fig. 5 ). Yellow; tergites with black transverse bands on middle of anterior portions of segments 1­7, without lateral black spots; tergites with sparse short white hairs dorsally, longer and denser laterally; venter yellowish white.

Genitalia ( Fig. 11 ). Mostly unsclerotized; clear, apical portion of spermatheca flat, mushroom­shaped, leading to long, thin, milky white tubular portion; apical spermathecal duct extremely long, thin, about 5 x length of sperm pump; sperm pump small, clear, bulbous basally with flared apical valve; basal spermathecal duct short, ca. one­half length of sperm pump. Dissection revealed approximately 50 ovariole eggs, each egg ca. 0.25 mm in length, white, without evident chorionic sculpturing.

Male. Unknown.

Types. Holotype female and 2 paratype females from: NAMIBIA: [Bethanien], Riverside 135 , SE 2616 Ca, 12–16 October 1971, Malaise trap [collector unknown] ( NMNW) . Holotype and paratypes deposited in NMNW.

Figures

FIGURES 5 ­ 8. Onchopelma, dorsal view (wings removed), showing color pattern of head, thorax, and abdomen. 5. O. majus, sp. n. female. 6. O. nitidum, sp. n., female. 7. O. pulchellum Hesse, female allotype. 8. O. trilineatum Hesse, female paratype.

FIGURES 10 ­ 11. Onchopelma female genitalia. 10. O. brevifasciatum, sp. n. 11. O. majus, sp. n.