Helina flavoextrema, Couri & Pont & Daugeron, 2010

Couri, Marcia S., Pont, Adrian C. & Daugeron, Christophe, 2010, The Muscidae (Diptera) of New Caledonia 2503, Zootaxa 2503 (1), pp. 1-61 : 34-35

20. Helina flavoextrema , sp. nov.

( Figs 27–33 )

Holotype. Male holotype, deposited in BPBM, labelled: New Caledonia: Pouébo: seashore, 0–20 m, 30.i.1964, R. Straatman.

Diagnosis. A non-metallic, grey dusted species; dorsocentrals 2+3; prealar present, much shorter than posterior notopleuron; meron bare; scutellum bare on sides and on ventral surface; cross-veins clear; halter yellow; legs yellow with tarsi brown; fore tibia without a submedian posterior seta; hind tibia with a short posterodorsal seta near base; extreme apex of abdominal tergite 5 pale yellowish.

Description. General colour. Ground-colour brown with grey pollinosity. Head with frons brown; frontoorbital plate and gena silvery pollinose. Antenna brown; pedicel with yellow areas in some specimens. Arista brown. Palpus brown. Scutum with two faint presutural brown stripes between dorsocentral row of setae, extending a little behind suture in some specimens, and, in female, with a pair of equally faint vittae outside the dorsocentral rows. Calypters yellowish and halter yellow. Wing clear. Legs yellow with brown tarsi. Abdomen with tergites 3 and 4 with two small round medio-lateral marks, those on tergite 3 more visible; extreme apex of abdominal tergite 5 pale yellowish.

Male. Length. Body: 4.5 mm, wing: 4.8 mm

Head. Frons at narrowest point about 3 times diameter of anterior ocellus. Ocellar seta long. Frontal row with 1 pair of strong setae close to lunula, followed by 4 pairs decreasing in size above. Antenna inserted at mid level of eye; postpedicel about 1.8 times as long as pedicel. Arista with long plumes, the longest individual plumes much longer than width of postpedicel. Palpus filiform. Vibrissa strong.

Thorax. Acrostichals 0+1; dorsocentrals 2+3; 2 postpronotals; 1 presutural; 2 intraalars; 2 supraalars; 2 postsupraalars. Notopleuron with two setae, the posterior one a little shorter than the anterior; without groundsetulae. Prealar present, much shorter than posterior notopleural. Postalar declivity and suprasquamal ridge bare. Anepisternum with a series of 5 long setae. Katepisternals 2+2, the upper ones long and the lower ones short. Anepimeron bare. Scutellum with a basal and an apical pair of setae, both long and similar in size, the apical one preceded by a short preapical. Lower calypter round, about twice as long as upper one. Wing veins bare. Costal spine strong, as long as cross-vein r-m. Fore femur on posterodorsal and posteroventral surfaces with a row of long setae, dorsal row sparser and a little shorter than ventral one. Fore tibia without submedian setae, with a posterodorsal and a dorsal apical seta, the dorsal longer. Mid femur on anterior to anterodorsal surface with a row of 6 setae on basal half, posteroventral surface with 3 sparse fine setae on basal third, 1 anterodorsal and 3 posterodorsal to posterior preapical setae. Mid tibia, with 2–3 posterior setae on middle third, apical setae on almost all surfaces, the ventral one longer than the others. Hind femur with a complete anterodorsal row of setae; anteroventral surface with a sparse row of setae, increasing in length towards apex. Hind tibia with 3 anterodorsal setae on middle third, 2 anteroventrals, and a short posterodorsal near base, anterodorsal and dorsal preapical setae present, the latter long, and an anteroventral apical.

Abdomen. Syntergite 1+2 and tergite 3 with 2–3 pairs of long and fine setae, tergites 3–5 each with 2–3 pairs of lateral setae, tergites 4 and 5 with a marginal row of long setae, tergite 5 also with a discal row. Sternite 1 bare. Sternite 5 as in Fig. 27 .

Terminalia. Cercal plate and surstylus as in Figs 28 and 29 ; aedeagus as in Fig. 30 .

Female. Length. Body: 4.5–5.0 mm, wing: 4.5–4.8 mm

Very similar to the male, differing as follows: frons at vertex about 1/3 of head-width; 3 strong inclinate frontal setae and 2 reclinate orbitals. Frontal triangle dusted, rather weak, almost reaching lunula. Fore femur with the apex of anterior surface expanded into a small scale. Mid femur with the posteroventral setae stronger. Setae on abdomen much less developed.

Ovipositor and spermatheca as in Figs 31 and 32 . Egg as in Fig 33 .

Discussion. The combination of characters given in the diagnosis above does not fit any of the described Australasian and Oceanian species. There is no available key in the literature for the identification of all the Helina species recorded from these Regions. The most useful are by Malloch (1925c), who keyed 30 species from Australia, and by Shinonaga & Kano (1984), who described and keyed 11 new Helina from Papua New Guinea all of which have the prealar seta much longer than the posterior notopleural seta.

Etymology. The name is derived from the Latin words flavus, meaning yellow, and extremus, meaning apex, and refers to the extreme yellow apex of the abdomen.

Material examined (all paratypes): BPBM: New Caledonia: La Crouen : iii.1959, 1 ♀ , N.L.H. Krauss ( BMNH). Monts Koghis : 500 m, 23–27.viii.1967, 1 ♂ , M. Sedlacek ( MNRJ). Pouébo : NE coast, 10 m, 11.i.1964, 1 ♂ , R. Straatman; 0–20 m, seashore, 30.i.1064, 2 ♀. Yiambi: NE, 1–50 m, 15.x.1967, 1 ♀, J. & M. Sedlacek. Isle of Pines: 7 Km N Kuto, 30–100 m, 16.viii.1979, mesic forest understory, 1 ♀ , W. C. Gagné (MNRJ) . Loyalty Islands: Lifou: ii.1962, 1 ♀ , N.L.H. Krauss ( MNHN). Mare: La Roche, iii.1959, 1 ♀

Distribution. New Caledonia ( New Caledonia, Isle of Pines, Loyalty Is).

Figures

FIGURES 27–34. 27–33. Helina flavoextrema, sp. nov. 27–30. Male terminalia. 27. Sternite 5. 28. Cercal plate and surstylus, dorsal view. 29. Cercal plate and surstylus, lateral view. 30. Aedeagus, lateral view. 31–33. Female. 31. Ovipositor, dorsal view. 32. Ovipositor, ventral view and spermathecae. 33. Egg, lateral view. 34. Limnophora longiantennata, sp. nov., ovipositor, lateral view and spermatheca.