Empis (Coptophlebia) tissoti sp. nov.

(Fig. 3)

Type material. HOLOTYPE ♂. France, Monéteau (89263), Bois de grand Pien, 47.8678, 3.5953, 110 m, 13.viii.– 14.x.2024, R. Decoin, TM 197, wooded fen, MNHN, ED13477. PARATYPE: 1 ♂ with same data as holotype, coll. DL.

Etymology. In honor of Bruno Tissot, recognizing his strong involvement in the development of knowledge of Diptera in the network of French nature reserves and beyond.

Diagnosis. Small greyish species (4 mm) belonging to the subgenus Coptophlebia, with vein M 1 complete, epandrium with a long dorsal projection, dusted thorax and shiny abdomen, white abdominal pubescence mixed with black setae in the centre of the tergites, brownish halter with brown stem, and black laterotergite fan; anal vein indistinct at middle, wing clear, less visible veins in the lower part; strongly curved and recurrent phallus; female unknown.

Distribution. France: Burgundy (89) (Fig. 4).

Description. Male (Fig. 3A, B). Head. Occiput dull black, black setae, postoculars curved towards front; pale postgena hairs and setae. Eyes holoptic with upper ommatidia enlarged. Frons reduced to small triangle above antennae; ocellar triangle shiny. Face and clypeus shiny brown. Antenna dull, brownish; scape as long as but thinner than rounded pedicel; postpedicel 3.5 times longer than width at base, 4 times length of scape, 1.5 times length of stylus. Proboscis pale, labrum dark and shiny, 1.5–2 times head height; long and slender labellum, dark and shiny; palpus dusted, dark with apical black bristly-hair.

Thorax dull black with grey pruinosity. Antepronotum with row of short black setae. Proepisternum with a few short dark setae. Postpronotum with one long black seta and shorter and thinner white ones. Acrostichals irregularly biserial, absent in prescutellar depression; dorsocentrals irregularly biserial, longer than acrostichals, ending in 3 strong, long setae in prescutellar depression. Laterotergite with fan of black setae. Scutellum with 2 long apical setae. Other strong, long black setae as follows: 2 presutural supra-alars, 3 notopleurals, 1 postsutural supra-alar, 2 postalars including small one.

Legs dark brown, shiny, very slightly dusted. Fore and mid coxae dull with white hairs and setae; hind coxa dull with brown setae. Fore femur with short, dorsal brown setae, less numerous, thinner and longer ventrally but shorter than femur depth; fore tibia with anterodorsal and posterodorsal rows of distinct setae longer than tibia depth, longer apically, with ventrals much shorter; tarsomeres with dorsal setae, longer apically, shorter ventrally. Mid femur with short setae mixed with 1 row of anterodorsal setae 2 times longer than femur depth, 2 rows of anteroventral and posteroventrals 3 times longer than femur depth, becoming shorter apically; mid tibia with short hairs dorsally mixed with 3 strong dark setae, 3 times longer than tibia depth and 2 rows of anteroventral and posteroventral setae as long as tibia depth; mid tarsomeres with short setae, longer apically. Hind femur with short brown setae dorsally mixed with 2 rows of anterodorsal and posterodorsal setae as long as femur depth, 2 rows of thinner anteroventral and posteroventral setae as long as femur depth and less numerous; hind tibia basally slender, stouter towards tip, dorsally with short setae mixed with 5–6 dark setae slightly longer than tibia depth, one row of anteroventral setae slightly shorter than tibia depth; hind tarsomere 1 somewhat swollen but thinner than tibia at tip, ventrally with setae as long as depth of metatarsus, longer dorsally, remaining tarsomeres with rather short setae, longer apically.

Wing (Length = 3.8 mm) very clear, veins less visible in basal area, inconspicuous small yellow pterostigma.Anal vein partly indistinct between middle and costa. Halter brownish although pale in Figure 3A due to reverberation of lamp on specimen in alcohol (with dried specimen, halter clearly brownish), with darker stem; calypter pale with fringe of white and brown hairs.

Abdomen shiny dark brown, 2 anterior sternites dusted.Abdominal hairs white ventrally and on sides of tergites, as long as postpedicel, white hairs 2 times shorter on tergites, mixed with shorter black setae in center of tergites, longer on tergite 1.

Hypopygium shiny dark brown (Fig. 3B); cercus with dorsal fan of short brownish hairs, slightly longer than epandrial lamella; epandrial lamella triangular and rounded posteriorly, as high as wide, with a few brown setae on posterior margin, hiding most of cercus, linked by broad dorsal sclerite, each lamella with long dorsal projection surmounted by dense fringe of dark setae; hypandrium forming broad ventral plate with narrow apex inserted inside widening of phallus; phallus dark brown, bumpy at exit of hypandrium, then thinner, paler and strongly bent forwards over cercus.

Female. Unknown.

Remarks. The subgenus Coptophlebia is very close to the subgenus Empis. The species were for a long time differentiated by the abbreviation of vein M 1 (Collin 1961; Chvála 1994). Daugeron et al. (2011) considered the abbreviation of vein M 1 should no longer be used to define taxonomic units within Empidinae. Empis tissoti sp. nov. is part of those Empis (Coptophlebia) species which have vein M 1 complete. It doesn’t belong to the Empis (C.) hyalipennis -group (Daugeron et al. 2011), because of the presence of acrostichals. Its strongly curved phallus is close to that of Empis (C.) abbreviata Loew, 1869 (Engel 1956, fig. 213) whose vein M 1 can be “ complete on both wings and reaching the wing-margin as in Empis s. str. ” (Chvála 1994). But E. abbreviata has the epandrial lamella without long dorsal projection. Empis (C.) hyalea -group (Daugeron & Grootaert 2005) is distributed almost everywhere in the world but only reaches the Palaearctic in Japan. Like E. tissoti sp. nov., species of this group have the epandrial lamellae linked by a broad dorsal sclerite, some species have also the epandrial lamellae with a long dorsal projection. Another autapomorphic character of this group is the presence of an unsclerotized zone in the middle of labella, E. tissoti sp. nov. doesn’t have such character. Its epandrium with such a long dorsal projection is presently unique among European Empis s. str. or Coptophlebia species.