Ammothereva nuda, Liu, Si-Pei, Gaimari, Stephen D. & Yang, Ding, 2012

Liu, Si-Pei, Gaimari, Stephen D. & Yang, Ding, 2012, Species of Ammothereva Lyneborg, 1984 (Diptera: Therevidae: Therevinae: Cyclotelini) from China, Zootaxa 3566, pp. 1-13 : 4-5

Ammothereva nuda sp. nov.

( Figs. 1–11 , 35 )

Diagnosis. Frons densely silver pruinose, but without any pile or setae. Antenna entirely yellow. Macrosetae on thorax black. Hind femur yellow. Abdominal tergites 2–3 yellow, each with a dark brown central spot. Epandrium as long as wide with distinct posterolateral flange. Outer gonocoxal process long and narrow. Aedeagus with dorsal apodeme wide.

Description. Male. Body length 9.2 mm, wing length 6.4 mm.

Head ( Fig. 1 ) with dense pale pruinescence over black ground color; frons covered with dense silver pruinescence, upper frons light brown. White pile from gena to occiput, upper occiput with some black postocular setae; ocellar tubercle, frons and parafacial bare. Eyes nearly contiguous on upper frons. Antenna ( Fig. 2 ) yellow with pale pruinescence; black setae on scape thick, several being very strong, but those on pedicel and basal first flagellomere short and thin; scape conical; pedicel ovoid; first flagellomere swollen in basal part and wider than scape and pedicel; style apical with tiny distal spine; antennal ratio 1.3: 1.0: 5.0: 0.9. Proboscis brownish yellow with brown pile; palpus yellow with yellow pile.

Thorax with dense pale pruinescence over black ground color; mesonotum with 2 pale yellow vittae. Notum and pleuron nearly bare, with only sparse short white pile; prosternum bare; macrosetae on thorax black, scutal chaetotaxy (pairs): np 3, sa 2, pa 1, dc 1, sc 2. Coxae and trochanters yellow with pale pruinescence; hind femur yellow, hind tibia yellow with dark brown tip, hind tarsomere 1 yellow with dark brown apex, other hind tarsomeres dark brown, hind pulvilli dark brown (fore and mid legs broken off, so further information not available). Coxae and trochanters with white pile and yellow setae, posterior surface of mid coxa bare; hind femur, tibia and tarsus with black setae. Fore coxa with a 1, av 1; mid coxa with a 2; hind coxa with a 3–4, d 1. Hind femur with av 5, pv 3. Hind tibia with ad 14, pd 9, av 8, pv 6, apically with 5 setae. Wing ( Fig. 4 ) hyaline, tinged yellow; pterostigma very narrow, brown, at end of R1; veins yellow in basal half of wing, becoming brown in distal half; cell m3 closed with a short petiole apically. Halter stalk brown in basal half, becoming yellow distally; knob yellow.

Abdomen yellow with pale pruinescence, except basal parts of segments 3–7 dark brown; covered with sparse short yellow pile mixed with short black recumbent pile; tergites 2–3 each with dark brown median spot. Terminalia yellow. Male genitalia: Epandrium ( Fig. 8 ) as long as wide, with distinct posterolateral flange, a dark brown bell-shaped spot in central area. Subepandrial sclerite with a shallow medial invagination, slightly shorter than cercus distally. Hypandrium short. Gonocoxite ( Fig. 9 ) with long and narrow outer gonocoxal process; ventral lobe triangular. Gonostylus elongated, nearly 3 times longer than wide. Dorsal apodeme of parameral sheath ( Fig.

10) wide, nearly 5 times wider than ventral apodeme; ventral apodeme short and narrow; distiphallus ( Fig. 11 ) long and curved ventrally.

Female. Unknown.

Type material. Holotype male, CHINA: Inner Mongolia, Helan Mountain, Yaoba, Xiazigou (39°00'N, 105°50'E), 30. VII. 2010, Li-Hua Wang.

Distribution. Palaearctic: China (Inner Mongolia) ( Fig. 35 ). This is biogeographically part of the Mongolia- Xinjiang Region ( Zhang 1999).

Remarks. This new species is similar to A. splendida ( Kröber 1912) in having the black antennal setae, the black mesonotal macrosetae and the relatively wide dorsal apodeme of the aedeagus. But it can be separated from it by the following features: frons bare without any pile or setae; hind femur totally yellow; tergites 2–3 each with a dark brown central spot; epandrium as long as wide; outer gonocoxal process distinctly narrow; distiphallus directly downcurved. In A. splendida , the frons has the blackish pile as long as width of the scape; the femora are brownish black; tergite 2–5 each have the large brownish black triangular areas in the middle; the epandrium ( Lyneborg 1984: 210, fig. 12) is 1.2 times longer than wide; the outer gonocoxal process ( Lyneborg 1984: 210, fig. 11) is wide basally and gradually tapers distally; the distiphallus ( Lyneborg 1984: 210, fig. 13) is dorsally recurved basally before turning ventrally.

The species Ammothereva mongolica ( Zaitzev, 1970) is not in the key, because only the female is known. Despite this species sharing the characteristic of having black mesonotal setae, the new species differs in having the coxae ( Fig. 3 ) and hind femur yellow. In A. mongolica , the coxae and hind femur are black.

Etymology. The specific name refers to the bare frons; from the Latin adjective “nudus” meaning bare or naked; a feminine adjective.

Figures

FIGURE 35. Distribution of Ammothereva species in China.

FIGURES 1 – 4. External morphology of male Ammothereva nuda sp. nov. 1. head, frontal view; 2. head, lateral view; 3. thorax, lateral view; 4. wing.

FIGURES 5 – 11. Male genital morphology of Ammothereva nuda sp. nov. 5. terminalia, lateral view; 6 tergite 8; 7. sternite 8; 8. epandrial complex, dorsal view; 9. gonocoxal complex, dorsal view; 10. aedeagus, ventral view; 11. aedeagus, lateral view. Scale: 0.2 mm.