Thinophilus saegeri, Grichanov, 2023

Grichanov, Igor Ya., 2023, A review of the Afrotropical Thinophilus Wahlberg, 1844 (Diptera: Dolichopodidae), with the descriptions of ten new species, European Journal of Taxonomy 878, pp. 1-52 : 27-29

Thinophilus saegeri sp. nov.

urn:lsid:zoobank.org:act:983B1BFE-4584-431B-BA98-C9CB86C0C58F

Fig. 8

Diagnosis

Thinophilus saegeri sp. nov. is very close to the Palaearctic Thinophilus versutus , differing in the following characters: palp yellow; antenna black; arista-like stylus dorsal; upper and lower propleural bristles white; wing without distinct dark spots; ratio of dm-m to distal part of M 4, 0.2/0.25; hypopygium with black cercus. Thinophilus versutus male has the following characters: palp black; antenna brown-black, yellow ventrally; arista-like stylus apical; upper and lower propleural bristles black; wing with distinct dark spots on dm-m and M 1+2; dm-m about half as long as distal part of M 4; hypopygium with yellow cercus ( Parent 1938; Negrobov 1979).

Thinophilus saegeri sp. nov. is also close to the Thinophilus cilifemoratus complex, differing in the following characters: femora mostly brown; coxae with black setae and bristles; fore femur with few short black setae at base, half as long as femur height; hypopygium with black cercus. Thinophilus cilifemoratus male has the following characters: femora yellow; coxae with yellow setae and bristles; fore femur with partly doubled ventral setae, longer than femur height; hypopygium with yellow cercus ( Becker 1902; Negrobov 1979; Grootaert & Meuffels 1998).

Etymology

The specific epithet is dedicated to the holotype collector, the Belgian entomologist Dr Henry De Saeger (RMCA).

Material examined

Holotype DR CONGO • ♂; “Congo Belge; P.N.G. [Parc National Garamba]; Miss. H. De Saeger; II/hd/4; 23 Mar. 1951; H. De Saeger leg.; 1444”; RMCA.

Description

Male ( Fig. 8A )

MEASUREMENTS. Body length 2.2 mm; antenna length 0.7 mm; wing length 2.2 mm; wing width 0.8 mm.

HEAD ( Fig. 8D ). Postcranium and frons, face and clypeus bluish black, grey pollinose; face under antennae 1.8 × as wide as height of postpedicel; clypeus half as long as epistoma, as wide as long; palp yellow, bearing black bristly hairs; proboscis black; 2 diverging ocellars; 1 vertical, 1 postvertical (all broken), not in row with upper postoculars; upper postoculars uniseriate, black; middle and lower postoculars biseriate, white, relatively long; antenna black ( Fig. 8B ); scape small, with short inner projection; pedicel simple, convex on inner side; postpedicel rounded, with short pubescence, higher than long (10/7); arista-like stylus dorsal, black, thick basally, thin distally, pubescent; length ratio of scape to pedicel to postpedicel to stylus, 0.08/0.06/0.07/0.56.

THORAX. Bluish black; no acrostichals; 4 dorsocentrals of almost equal length; scutellum with 2 strong marginals; no laterals; few white upper and lower propleural bristles of different length.

LEGS. Fore coxa brownish yellow; mid and hind coxae black; legs mostly brownish yellow; femora darker and tibiae lighter; tarsi brown-black from tip of basitarsus.

FORE LEG. Coxa with black setae and bristles; femur simple, with few short black setae at base, half as long as femur height; tibia and tarsus simple; tibia with 1 anterodorsal, 3 short apicals; segment 5 weakly widened; length of femur, tibia and tarsal segments (in mm): 0.73/0.71/0.33/0.18/0.15/0.11/0.10.

MID LEG. Coxa with black setae; femur with anteroventral row of dark setae, at most half as long as femur height, and few posteroventrals at apex; tibia bearing 1 anterodorsal and 2 posterodorsal bristles, 3 apicals; tarsal segment 5 inconspicuously thickened; length of femur, tibia and tarsal segments (in mm): 0.83/0.95/0.49/0.23/0.18/0.1/0.11.

HIND LEG. Coxa with 1 black exterior bristle; femur with anteroventral row of setae, ⅓ × as long as femur height; tibia with rather short setae; segments 3–5 broken; length of femur, tibia and tarsal segments (in mm): 0.96/0.97/0.28/0.28/-/-/-.

WING ( Fig. 8C ). Fumose, without darker shades; veins yellow-brown; distal part of M 1+2 straight; R 4+5 almost parallel with M 1+2; ratio of part of costa between R 2+3 and R 4+5 to that between R 4+5 and M 1+2 (in mm), 0.36/0.17; crossvein dm-m straight; ratio of dm-m to distal part of M 4, 0.2/0.25; anal vein distinct; halter with yellow stem and brown knob; lower calypter dirty yellow, with white cilia.

ABDOMEN ( Fig. 8E ). Black, grey pollinose; setae and hind-marginal bristles on tergites black, short; sternites with short setae. Hypopygium (lost during maceration) black, cercus black, short, as long as tergite 5, covered with light setae.

Female

Unknown.

Figures

Fig. 8. Thinophilus saegeri sp. nov., holotype, ♂ (RMCA). A. Habitus. B. Antenna. C. Wing. D. Head. E. Abdomen, ventral-lateral view, dry.