Helina longicerca, Couri, Márcia & Pont, Adrian, 2016

Couri, Márcia & Pont, Adrian, 2016, New African species of Helina Robineau-Desvoidy (Diptera, Muscidae), Zootaxa 4103 (4), pp. 374-382 : 378

Helina longicerca sp. nov.

( Figs. 2 , 9–12 )

Type material examined. Holotype male. NIGERIA: Mambilla, Plateau, Ngel Nyaki, 28.xi.–3.xii.1968, J. C. Deeming / montane forest, c. 5500 ft. Paratypes, 4 males (1 MNRJ, 1 OUMNH), same labels as holotype.

Diagnosis. Scutum almost all dark brown shining, except for grey pollinose postpronotum and notopleuron, two small lateral areas close to suture and an irregular grey pollinose band before scutellum ( Fig. 2 ); anterior postsutural intraalar setae absent; prealar seta absent; lower katepisternal seta fine and inserted closer to posterior than to anterior seta; fore tibia without a posterior median seta; mid tibia without anterodorsal seta; hind tibia without a posterodorsal seta; wing clear.

Description. General colouration. Brown with grey pollinosity. Frons dark brown; fronto-orbital plate, face, parafacial and gena silvery-grey pollinose; antenna dark brown; arista brown; palpus dark brown; scutum almost wholly dark brown, shining, except for grey pollinose postpronotum and notopleuron, two small lateral areas close to suture and an irregular grey pollinose band before scutellum ( Fig. 2 ); calypters slightly infuscated, with brown margins; haltere yellow with knob whitish; wing clear; legs brown, mid and hind tibiae yellowish on apical two thirds; abdomen uniformly brown with grey pollinosity.

Male. Body length: 6.8–7.0 mm; wing length: 7.2 mm.

Head. Holoptic; eye bare; 8–10 pairs of frontal setae on whole length of frons, the seta closest to lunule longer and the uppermost one reclinate; inner and outer vertical setae ciliform; ocellar setae short; antenna inserted at midlevel of eye; postpedicel about twice the length of pedicel; arista long-plumose; palpus filiform.

Thorax. Dorsocentral setae 2+3, the anterior presutural short, all others long and similar in size; acrostichals 0+1; 2 postpronotals; 1 presutural and 1 postsutural intraalar, the anterior postsutural seta absent; prealar absent; 1 supraalar; 1 postalar; notopleuron with 2 setae, the posterior slightly shorter than anterior; anepisternum with a series of 5 long setae, and one in dorsal anterior corner; katepisternals 1+2. Scutellum with 1 long basal and 1 long apical pair of setae, similar in length; margins and ventral surface bare.

Legs. Fore femur with rows of posteroventral and posterodorsal setae; fore tibia without a median posterior seta, 1 preapical dorsal and 1 ventral apical; mid femur with 3 well-spaced ventral setae on basal half and 2 preapical dorsals; mid tibia with 2 posterior setae on middle third, 1 short dorsal preapical, and apical setae on posteroventral, anteroventral and ventral surfaces, the last two longer and similar in size; hind femur with complete rows of anterodorsal and anteroventral setae, those in anteroventral row more spaced, posterodorsal surface with a seta at apical fifth; hind tibia with 2 anterodorsals on middle third and 2 anteroventrals, one median and one supramedian, 1 anterodorsal and 1 posterodorsal preapicals, and 1 ventral apical.

Wing. Veins bare; veins R4+5 and M parallel at wing-tip; costal spine not distinct; lower calypter about 1.8 times the length of upper one.

Abdomen. Syntergite 1+2 and tergite 3 with lateral setae; tergite 4 with 2–3 pairs of lateral setae; tergites 4 and 5 each with a discal and a marginal row of setae; sternite 1 bare; sternite 5 with 2 strong setae on each lobe ( Fig. 9 ).

Terminalia . Cercal plate twice longer than wide; surstylus long ( Figs 10–11 ). Aedeagal complex as in Fig. 12 .

Female. Unknown.

Distribution. Nigeria (Mambilla Plateau).

Etymology. The specific epithet longicerca is derived from the Latin longus (“long”) and cercus (“cercal plate”), and refers to the long cercal plate.

Notes. The new species runs to couplet 9 and H. juxtamedialis Emden in Emden’s (1951) key, but in this species the scutum is densely dusted with two pairs of vittae.

Figures

FIGURES 1 – 4. Dorsal view of holotypes: (1) Helina duocolorata sp. nov., holotype male; (2) Helina longicerca sp. nov., holotype male; (3) Helina mediomaculata sp. nov., holotype male; (4) Helina sexnotata sp. nov., holotype female.

FIGURES 5 – 12. (5 – 8) Helina duocolorata sp. nov., male: (5) sternite 5, dorsal view; (6) cercal plate and surstyli, dorsal view; (7) cercal plate and surstyli, lateral view; (8) aedeagal complex, lateral view. (9 – 12) Helina longicerca sp. nov., male: (9) sternite 5, dorsal view; (10) cercal plate and surstyli, dorsal view; (11) cercal plate and surstyli, lateral view; (12) aedeagal complex, lateral view.