Hercostomus fedotovae, Grichanov, 2020

Grichanov, Igor Ya., 2020, New species of Hercostomus Loew, 1857 from Afrotropics (Diptera: Dolichopodidae) and key to Afrotropical fauna, European Journal of Taxonomy 722, pp. 16-36 : 20-22

Hercostomus fedotovae sp. nov.

urn:lsid:zoobank.org:act:90F6AB29-BADE-4A85-B45E-F187894798A1

Fig. 2

Diagnosis

The new species belongs to the Hercostomus nectarophagus subgroup of species, differing distinctly by its small size, narrow face, fore tarsomere 3 simple, fore tarsomeres 4–5 flattened and widened, fore tarsomere 4 white and tarsomere 5 deep black. The hypopygium is similar to that in other species of the subgroup.

Etymology

The species is named for the Russian entomologist, Dr. Zoya Fedotova (VIZR: All-Russian Institute of Plant Protection, St. Petersburg), who has described over 1000 new gall midge species.

Material examined

Holotype

TANZANIA • ♂; Morogoro environs; 6.85° S, 37.67° E; 2–3 Dec. 2015; N. Vikhrev leg.; terminalia dissected, stored in glycerin in microvial pinned with the specimen; ZMUM.

Description

Male ( Fig. 2 )

MEASUREMENTS (in mm). Body length 2.4; antenna length 0.7; wing length 2.5; wing width 0.8. ( Fig. 2A )

HEAD. Frons greenish-black, whitу pollinose; face densely white pollinose. One long, strong, vertical pair of ocellar setae; 1 short postvertical, pair of ocellar setae. Upper postocular setae black; lateral, lower ones white. Eye with short hairs; face glabrous. Face gradually narrowed towards palpi, 14 × as high as wide in middle, under antennae ¾ as wide as width of postpedicel, at clypeus ¼ as wide as width of postpedicel; clypeus not reaching lower margin of eyes. Antenna ( Fig. 2B ) as long as height of head, entirely black; pedicel short and wide, convex anteriorly on inner side, with short distal setulae; postpedicel subtriangular, angular distodorsally, as long as high, covered with short pubescence; arista mid-dorsal, black, with short hairs. Length ratio of scape to pedicel to postpedicel to stylus (1 st – 2 nd segments), 14/6/12/7/47. Palpus and proboscis moderately small, brown, with short black setae; palpus with 1 black bristle.

THORAX. Greenish-black, greyish pollinose, with yellow metepimeron. Six strong dorsocentral setae; 2 rows of acrostichals, nearly half as long as dorsocentrals; 2 strong notopleural, 1 strong humeral, 1 posthumeral setae present. Propleura with 1 strong black seta above fore coxa and few short hairs. Scutellum with 2 strong setae and 2 lateral hairs.

LEGS. Including coxae yellow; fore tibia and segments 1–3 of fore tarsus brownish; segment 4 white with black apex, segment 5 black; mid and hind tarsi black from tip of basitarsus; fore coxa with black hairs anteriorly and several setae in apical half; mid coxa with 1 strong lateral setae in addition to anterior hairs; hind coxa with 1 strong lateral setae; femora without long hairs; fore tibia without distinct setae; segments 1–3 of fore tarsus with ventral row of sparse short curved hairs; segment 4 flattened laterally, slightly widened, covered with white hairs and several black setae, segment 5 flattened laterally, strongly widened, with dorsal row of black flattened setae ( Fig. 2C ). Length of fore femur, tibia and tarsomeres 1–5 = 0.93 mm, 0.99 mm, 0.51 mm, 0.46 mm, 0.34 mm, 0.16 mm, 0.17 mm. Mid femur with 1 anterior and 1 posteroventral subapical setae; mid tibia with 1 anterodorsal, 2 posterodorsal and 3–4 apical setae. Length of mid femur, tibia and tarsomeres 1–5 = 0.98 mm, 1.28 mm, 0.65 mm, 0.35 mm, 0.31 mm, 0.2 mm, 0.15 mm. Hind femur with one subapical anterior seta; hind tibia with 2–3 anterodorsal, 2–3 posterodorsal, 2–3 fine ventral, 3–4 apical setae, thick brown-black apical spine anteriorly; segment 1 of hind tarsus with basal excavation anteriorly. Length of hind femur, tibia and tarsomeres 1–5 = 1.12 mm, 1.48 mm, 0.42 mm, 0.53 mm, 0.29 mm, 0.2 mm, 0.16 mm.

WINGS. Simple, greyish, veins brown. Costa simple. R 1 reaching to first third of wing length. R 2+3, R 4+5 weakly divergent. Ratio of part of costa between R 2+3, R 4+5 to between R 4+5, M 1+2: 3/1. R 4+5, M 1+2 slightly convergent in distal part; M 1+2 with weak bend in middle of distal part, joining costa just before wing apex. Crossvein dm-m straight, almost perpendicular to longitudinal wing axis, forming right angle with M 1+2, M 4 longitudinal veins. Ratio of dm-m to distal part of M 4, 19/46. Posterior wing margin almost evenly convex. Anal vein distinct, almost reaching wing margin; anal lobe reduced; anal angle absent. Lower calypter yellow, brown anteriorly, with brown setae. Halter yellow.

ABDOMEN. Greenish-black, weakly pollinose, with black hairs and marginal setae. Segment 7 short, 4 ⁄ 5 length of epandrium. Segment 8 large, covering more than half lateral side of epandrium, with numerous fine short dark cilia. Genitalia ( Fig. 2 D–F) with epandrium brown-black, rounded-oval, twice longer than high. Foramen positioned before middle of left lateral side. Hypandrium mid-ventral, with short base, 4 long thick lobes of different lengths and widths; longest lobe wide, flat, thin, with pointed apex; thickest lobe of hypandrium strongly curved proximally, U-shaped (ventral view). Phallus thin, concealed. Distoventral epandrial lobe fused to epandrium, projected, with 2 short and 1 very long ventral epandrial setae. Surstylus yellow, small, bilobate; each lobe thick at base, thin distally, with 1 long basal seta and 1 short apical seta. Distal lobe of postgonite as long as cercus, broad, curved ventrally, pointed at apex ( Fig. 2F ). Ventral lobe of postgonite broad, subtriangular, strongly sclerotized, with serrate ventral margin ( Fig. 2D ). Cercus yellow, covered with light hairs; large basolateral lobe bearing 3–4 strong, several short setae, long narrow apex bearing 4 long pedunculate setae ( Fig. 2D ).

Female

Unknown.

Distribution

Tanzania.

Figures

Fig. 2. Hercostomus fedotovae sp. nov., ♂, holotype (ZMUM). A. Habitus. B. Antenna. C. Fore tarsus. D. Distal appendages of epandrium. E. Hypopygium, left lateral view. F. Hypopygium, right lateral view.