Homoneura (Homoneura) trilineata, Li & Yang, 2012

Li, Wenliang & Yang, Ding, 2012, Eleven new species of the Homoneura (Homoneura) beckeri group from Yunnan, China (Diptera, Lauxaniidae), Zootaxa 3537, pp. 1-28 : 26

Homoneura (Homoneura) trilineata sp. nov.

( Figs. 11, 22, 33, 90–95)

Diagnosis. Face without spots. Antenna blackish brown. Wing slightly yellow, without markings. Abdominal tergites 1–2 entirely black; tergite 3 mostly black except for yellow anterolaterally; tergites 4–6 each with a black median spot, confluent with black posterior bands on tergites 4–5.

Description. MALE. Body length 4.5 mm, wing length 4.3 mm.

Head ( Fig. 11) pale yellow. Face without spots. Frons about as long as wide and parallel–sided, with two narrow blackish gray stripes along or rows and a narrow brown triangular median stripe extending to ocellar triangle; ocellar triangle grayish black; oc strong, about as long as anterior or, anterior or slightly shorter than posterior or. Gena about 1/7 height of eye. Occiput with a wide grayish black stripe confluent with ocellar triangle. Antenna blackish brown, 1st flagellomere 1.6 times longer than high; arista long plumose, black except brownish basally, with longest hairs longer than height of 1st flagellomere. Proboscis yellowish brown, with yellowish and blackish hairs; palpus pale yellow with blackish hairs.

Thorax ( Fig. 22) blackish brown with grayish white pruinescence. Mesoscutum with white pruinescence on anterior margin, 0+3 dc (anterior dc clearly behind transverse scutal suture), acr in 8 somewhat irregular rows. Anepisternum blackish brown except yellow ventroapical corner, and pteropleuron blackish brown with whitish gray pruinescence. Scutellum brownish black except yellow apical margin, with yellowish gray pruinescence. Legs pale yellow, but all tarsi dark yellow except tarsomere 5 brown on apical half; hind tibia with an incomplete brown basal ring. Fore femur with 4 strong pv and 6 pd, ctenidium with 11–12 short bristles; fore tibia with 1 long preapical ad and 1 short apv. Mid femur with 5 a and 1 apv; mid tibia with 1 strong preapical ad and 3 strong apv. Hind femur with 1 preapical ad; hind tibia with 1 weak preapical ad and 1 short apv. Wing ( Fig. 33) slightly yellow, without markings; subcostal cell hyaline; costa with 2nd (between R 1 and R 2+3), 3rd (between R 2+3 and R 4+5) and 4th (between R 4+5 and M 1) sections in proportion of 2: 0.6: 0.4; r-m at middle of discal cell; ultimate and penultimate sections of M 1 in proportion of 1.3: 0.8; ultimate section of CuA 1 about 1/5 of penultimate. Halter pale yellow.

Abdomen yellow with sparse silvery white pruinescence; tergites 1–2 entirely black; tergite 3 mostly black except yellow anterolaterally; tergites 4–6 each with a black median spot, confluent with black posterior bands on tergites 4–5. Male genitalia ( Figs. 90–95): protandrium circular, with a long narrow furcated ventral process; epandrium nearly trapezoidal in lateral view, surstylus consisting of a digitiform process and a small curved coniform process; hypandrium with a long narrow ventral process, hypandrial apodeme distinct; gonopod columniform; aedeagus without apical incision, with a pair of lateral median teeth and two pairs of basal teeth.

FEMALE. Unknown.

Type material. Holotype ♂ ( CAU), CHINA, Yunnan Province: Baoshan, Baihualing, Wenquan (1500 m), 29. V. 2007, Xingyue Liu.

Distribution. China (Yunnan).

Remarks. The new species is somewhat similar to Homoneura (Homoneura) occipitalis Malloch from China (Taiwan) in the following characters: frons with two narrow blackish gray stripes along or rows and a narrow brown triangular median stripe extending to ocellar triangle; wing without distinct stripe; abdominal tergites 1–2 entirely black, tergite 3 mostly black except yellow at anterior lateral area. But it can be separated from the latter by the following features: face without spots; antennal 1st flagellomere entirely blackish brown; abdominal tergite 6 with a black median spot; protandrium with a long narrow furcated ventral process; surstylus consisting of 2 processes; aedeagus without apical incision. In H. (H.) occipitalis , the antennal 1st flagellomere is brownish black except pale yellow on ventral 1/3–1/2; the face has a pair of blackish brown elliptical spots; the abdominal tergite 6 has no spot in male; the protandrium has no ventral process; the surstylus is a incurved, stick–like process; the aedeagus has a deep apical incision ( Malloch 1927).

Etymology. Latin, trilineata , meaning trilinear, referring to the frons having 3 blackish gray stripes.