Helina sexnotata Couri & Pont, 2016, sp. nov.

Helina sexnotata sp. nov.

(Figs. 4, 17–20)

Type material examined. Holotype female. NIGERIA: Mambilla Plateau, Ngel Nyaki, 28.xi.–3.xii.1968, J. C. Deeming / overgrown cocoyam plots in village. Paratypes, 1 male (MNRJ), same labels as holotype (hind legs are missing).

Diagnosis. Scutum presuturally with 2 lateral dark brown spots and one broad median vitta; postsuturally with 3 more or less rectangular dark brown spots reaching from suture to second dorsocentrals (Fig. 4); both postsutural intraalar setae present; prealar absent; katepisternals 1:2; fore tibia with a posterior median seta; mid tibia without anterodorsal seta; hind tibia with a posterodorsal seta inserted at the border of apical and middle thirds; wing clear.

Description. General colouration. Brown with grey pollinosity. Frons brown; fronto-orbital plate, face, parafacial and gena silvery-grey pollinose; fronto-orbital plate in female with a brown spot just above lunule, surrounding 3 of the frontal pairs of setae; antenna dark brown, tip of scape with grey pollinosity; arista dark brown; palpus dark brown; scutum presuturally with 2 lateral dark brown spots and one broad median vitta; postsuturally with 3 more or less rectangular dark brown spots reaching from suture to second dorsocentrals (Fig. 4); scutellum dark brown with lateral margins grey pollinose; calypters white; haltere yellow; wing clear; legs dark brown, coxae light brown with grey pollinosity; abdomen with disc of tergites uniformly brown, but with grey pollinosity close to the posterior margins in males, in females the abdomen is grey pollinose with pairs of faint roundish brown spots on tergites 3 and 4 and a median brown vitta on tergites 4 and 5.

Female. Body length: 6.2 mm; wing length: 5.5 mm.

Head. Eye bare; frons at level of anterior ocellus about one third of head-width; 3 pairs of frontal setae, the pair closest to lunule very long, and with 2 pairs of reclinate orbital setae; inner vertical setae long, and outer vertical shorter than inner; ocellar setae moderate in length; antenna inserted at mid-level of eye; postpedicel about 2.5 times the length of pedicel; arista long-plumose; palpus filiform.

Thorax. Dorsocentrals 2+3, the anterior presutural shorter than the others; presutural acrostichals not differentiated; prealar absent; 2 postpronotals; 1 presutural and 2 postsutural intraalars, the anterior postsutural seta very short and the posterior seta very long; 1 presutural and 1 postsutural supraalar; 1 postalar; notopleuron with 2 setae, the posterior one slightly shorter than the anterior; anepisternum with a series of 5 long setae, and a long seta 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, posterior and posterodorsal setae; fore tibia with a median posterior seta, 1 preapical dorsal and 1 ventral apical; mid femur with 3 well-spaced ventral setae in basal half, 1 anterodorsal in apical fifth, and 2 preapical dorsals; mid tibia with 3 posterior setae on middle third, the median longer, apical setae on dorsal, posterodorsal, anterior and ventral surfaces, the latter longer; 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 submedian and the other below this, 1 anterodorsal and 1 posterodorsal preapicals, and 1 ventral apical.

Wing. Veins bare; veins R 4+5 and M parallel at wing-tip; costal spine distinct; lower calypter about twice the length of the upper one.

Abdomen. Syntergite 1+2 and tergite 3 with one pair of lateral setae; tergite 4 and 5 each with a discal and a marginal row of setae; sternite 1 bare.

Male. Body length: 6.5 mm; wing length: 6.3 mm.

Similar to female, except for: head holoptic; 3 pairs of frontal setae, all inserted on lower third of frons, the one closest to lunule longer; inner and outer vertical setae and ocellar setae moderate in length; sternite 5 with 3 strong and short setae on each lobe (Fig. 17).

Terminalia. Cercal plate as long as wide and surstylus as in Figs 18–19. Aedeagal complex as in Fig. 20.

Distribution. Nigeria (Mambilla Plateau).

Etymology. The specific epithet sexnotata is derived from the Latin sex (“six”) and notatus (“marked”), and refers to the six dark brown markings on scutum.

Notes. The new species runs to couplet 29 in Emden’s (1951) key, but does not agree with either of the two species included in this section, H. fasciata (Jaennicke) and H. lucida (Stein), as in the new species the prescutum has 2 lateral dark brown spots and one broad median vitta and the postscutum has 3 rather rectangular dark brown spots from the suture posteriorly until the level of second dorsocentral setae.