Genus Thinophilus Wahlberg, 1844

Thinophilus Wahlberg, 1844: 37 .

Type species: Rhaphium flavipalpe Zetterstedt, 1843 (monotypy).

Thinophilus Schiødte, 1844: 44 (nec Wahlberg, 1844).

Type species: Rhaphium flavipalpe Zetterstedt, 1843 (monotypy).

Schoenophilus Mik, 1878: 9 .

Type species: Thinophilus versutus Haliday, 1851 (original designation).

Pseudacropsilus Strobl, 1899: 122 .

Type species: Pseudacropsilus maculipennis Strobl, 1899 [= Thinophilus versutus (Haliday, 1851)] (designation by Negrobov 1991: 38).

Paralleloneurum Becker, 1902: 51 .

Type species: Paralleloneurum cilifemoratum Becker, 1902 (monotypy), syn. nov.

Parathinophilus Parent, 1932: 161 .

Type species: Parathinophilus expolitus Parent, 1932 (monotypy).

Notes

See diagnosis and discussion in Negrobov (1979) and Grootaert (2018).

Grootaert & Meuffels (1984, 1998) distinguished three subgenera of Thinophilus in the Australasian and Oriental Regions, i.e., Thinophilus s.s., Parathinophilus Parent, 1832 and Schoenophilus Mik, 1878, and noted that the differences between them are rather poor. Negrobov (1979) and Grootaert & Meuffels (1998) described Paralleloneurum, originally described from Egypt and known also from the Oriental Region. The authors provided only one reliable character, the presence of four pairs of strong dorsocentrals on the mesonotum, to distinguish this genus from Thinophilus with five or more dorsocentrals, either nearly equal in length or greatly decreasing in length anteriorly. Later, a lot of Oriental species of Thinophilus with four pairs of dorsocentrals were described by Grootaert and his co-authors (Grootaert et al. 2015; Samoh et al. 2017, 2019; Grootaert 2018); with some of these species having apical or dorsoapical arista on postpedicel. Nevertheless, the status of Paralleloneurum Becker, 1902, Parathinophilus and Schoenophilus was not discussed.

Negrobov (1979) described also Thinophilus versutus Haliday, 1851 in the genus Schoenophilus that was considered a subgenus or synonym of Thinophilus by some authors before and after 1979. He distinguished Schoenophilus from Thinophilus by the presence of only four pairs of dorsocentrals on the mesonotum and from Thinophilus and Paralleloneurum by apical or subapical arista on postpedicel.

Both Paralleloneurum and Schoenophilus are regarded here as synonyms of Thinophilus (see also Discussion section). Therefore, the following new combinations are here established: Thinophilus cilifemoratus (Becker, 1902), comb. nov. and T. pygmaeus (De Meijere, 1916), comb. nov. The latter species is known only from type locality in Indonesia (Java) (De Meijere, 1916). The status of the Australian subgenus Parathinophilus needs further study. As a result, the tribe Thinophilini includes now only two genera, Thinophilus and Machaerium Haliday, 1832 with three known species in the latter genus. Incompletely described Thinophilus aquaticus Becker, 1914 known by females from Kenya (Tiwi), is not included into the key below. Thinophilus atritarsis Parent, 1929 and T. tinctus Parent, 1929 known by females from South Eastern Desert of Egypt were included into the Afrotropical Catalog (Grichanov 2018), but they are excluded here from the Region. The Palaearctic T. quadrimaculatus Becker, 1902 is also excluded from the Afrotropical fauna (see below). Thinophilus atritarsis, T. tinctus and T. quadrimaculatus are inserted into the key to West and Central Palaearctic species of Thinophilus (Grichanov 2022) .

Key to Afrotropical species of Thinophilus Wahlberg, 1844 (males)

North African Thinophilus versutus and T. cilifemoratus comb. nov. are included in square brackets. See discussion for species groups and subgroups.

1. Mesonotum with four strong dorsocentrals of almost equal length; body length less than 2.5 mm 2

– Mesonotum with at least five dorsocentrals, usually greatly decreasing in length anteriorly; body usually longer than 3 mm ................................................................................................................. 7

2. Body and legs with only whitish yellow bristles (Fig. 6A); body: 1.7 mm ( T. gallagheri group) ................................................................................................................ T. gallagheri sp. nov.

– Body and legs with mainly black bristles ( T. versutus group) .......................................................... 3

3. Palp brown-black; propleural bristles black (Negrobov 1979: 436); body: 1.7–2.5 mm ................... .................................................................................................................[ T. versutus Haliday, 1851]

– Palp yellow; propleural bristles white .............................................................................................. 4

4. Male cercus long, reaching almost to base of abdomen (Fig. 3H); body: 2.0– 2.5 mm ...................... ..................................................................................................................... T. prudens Curran, 1926

– Male cercus short, about as long as tergite 5 .................................................................................... 5

5. Male fore femur with long ventral setae, 2 × as long as femur height; legs yellow; cercus yellow (Fig. 7A); body: 2.0 mm ....................................................................................... T. sigwalti sp. nov.

– Male fore femur with short ventral setae, not longer or slightly longer than femur height; legs and cercus yellow or dark ........................................................................................................................ 6

6 Legs mostly brownish yellow, with femora mostly brown; cercus black (Fig. 8A); body: 2.2 mm .. ................................................................................................................................ T. saegeri sp. nov.

– Legs mostly light yellow; cercus yellow (Negrobov 1979: 437); body: 1.5–2.0 mm......................... ....................................................................................................... [ T. cilifemoratus (Becker, 1902)]

7. Scutellum with two pairs of almost equal in length bristles; palp with white setae; body: 6.0 mm (female only) ........................................................................................... T. quadrisetus Parent, 1936

– Another combination of characters ................................................................................................... 8

8. Pedicel long, with broad distodorsal and narrow distoventral lobes (Negrobov 1978: figs 1384– 1385); sternite 4 of male abdomen with lateral groups of bristles (Dawah et al. 2020: fig. 5c); body: 5.0– 5.5 mm ............................................................................................... T. promotus Becker, 1910

– Pedicel without such lobes; sternite 4 of male abdomen with at most long hairs ............................ 9

9. Sternites 3 and 4 of male abdomen with tuft of long hairs (e.g., Fig. 3G) ( T. imperialis group) ... 10

– Sternites 3 and 4 of male abdomen without tuft of long hairs ........................................................ 12

10. Cercus flat and short, band-like (lateral view), pointed on apex, reaching apex of surstylus; Surstylus with one midventral process (Fig. 3 С); sternites 3 and 4 of abdomen with tuft of white hairs; body: 6–7 mm ............................................................................................... T. ciliventris Grichanov, 1997

– Cercus very long, extending to base of abdomen, broad on basal third, filiform distally; sternites 3 and 4 of abdomen with tuft of mainly black hairs ...........................................................................11

11. Fore tibia with 3–4 dorsal bristles, not longer than tibia width; surstylus at middle 2 × as wide as that at base (lateral view) (Fig. 3F); body: 5.5 mm ...................................... T. imperialis (Curran, 1924)

– Fore tibia with 3–4 dorsal bristles, 2 × as long as tibia width; surstylus at middle slightly wider than that at base (lateral view) (Fig. 9E); body: 6.3 mm ........................................ T. longicercus sp. nov.

12. Mesonotum with distinct dark lateral spot at notopleura (e.g., Dawah et al. 2020: fig. 5a) ( T. indigenus group) .............................................................................................................................................. 13

– Mesonotum monochrome, or with longitudinal stripes dorsally, without dark lateral spots, rarely with postalar dark spot .................................................................................................................... 16

13. Mesonotum with additional spot in front of scutellum ................................................................... 14

– Mesonotum without spot in front of scutellum ............................................................................... 15

14. Fore basitarsus without ventral spines, with simple setulae only (Dawah et al. 2020: fig. 5a); male genitalia as in Negrobov (1978: figs 1371–1373); body: 2.5–3.0 mm ..... T. indigenus Becker, 1902

– Fore basitarsus with row of very short spinules (Vanschuytbroeck 1951: fig. 20); body: 5.2– 5.8 mm .................................................................................... T. splendidus Vanschuytbroeck, 1951

15. Mesonotum with five dorsocentrals; legs mostly yellow; fore femur without ventral comb of setae; mid tibia curved at middle (Bezzi 1906: 302); body: 4 mm .................... T. setulipalpis Bezzi, 1906

– Mesonotum with at least six dorsocentrals; legs mostly black; fore femur with ventral rows of black setae (Curran, 1926: fig. 14); mid tibia simple; body: 5.0– 5.5 mm ..................... T. rex Curran, 1926

16. Scutellum with 3 to 8 pairs of strong marginal spines in addition to one pair of long bristles; tarsomeres 1 and 2 of hind tarsus annulate with yellow and black ( T. quadrisetus group, in part) 17

– Scutellum with at most two pairs of bristles; hind tarsomeres variously coloured ........................ 18

17. Fore coxa with black setae and pale hairs; fore femur with a few long black ventral hairs in basal third; scutellum with 6 to 8 pairs of spines (Fig. 4 С); body: 4.5–5.0 mm .......................................... .......................................................................................................... T. munroi munroi Curran, 1926

– Fore coxa and femur with pale hairs only; scutellum with 3 to 5 pairs of spines (Fig. 5 С); body: 4.5–4.7 mm ..................................................................... T. munroi setiscutellatus Grichanov, 1997

18. Male hind coxa with long straight apical spine (Dawah et al. 2020: fig. 5b); body: 4.0– 4.5 mm ................................................................................................... T. ochripalpis Becker, 1910

– Male hind coxa without spine ......................................................................................................... 19

19. Male fore basitarsus with nearly right-angled bend; mid femur with posteroventral setae in middle part, at least half as long as femur diameter; male genitalia as in Negrobov (1978: figs 1378–1380), Grichanov (1997: fig. 1); body: 3.9–5.5 ................................................... T. mirandus Becker, 1907

– Male fore basitarsus straight or fairly curved; mid femur with short or long setae in middle part 20

20. Palp with black setae; tarsi gradually darkened towards tarsomere 5 ( T. indigenus group mainly) ............................................................................................................................................ 21

– Palp with white setae; tarsomeres often more or less distinctly annulated ( T. calopus group) ...... 28

21. Fore basitarsus with ventral row of short but strong black spines, at least half as long as article diameter .......................................................................................................................................... 22

– Fore basitarsus without ventral spines, with simple setulae only ................................................... 23

22. Fore tarsomere 4with strong dorsal bristle, as long as or longer than tarsomeres 4 and 5 combined; male genitalia as in Negrobov (1978: figs 1393–1396); body: 3.7–5.4 mm .... T. spinitarsis Becker, 1907

– Fore tarsomere 4 with short setae; body: 4 mm ....................................... T. spinulosus Parent, 1929

23. Wing crossvein dm-m half as long as distal part of M 4 (Fig. 10F); fore tibia ⅓ longer than fore tarsus (4 /) (Fig. 10D–E); body: 1.8 mm ( T. deemingi group) ....................................... T. deemingi sp. nov. 3

– Wing crossvein dm-m as long as or ⅔ as long as distal part of M 4; fore tibia not longer than fore tarsus ............................................................................................................................................... 24

24. Antenna almost entirely yellow, brownish dorsally; femora with 2 more or less full rows of ventral setae, nearly half as long as femur height; cercus broad in middle, narrowed towards apex; dm-m as long as distal part of M 4 (Grichanov 2012: fig. 24); body: 3.5 mm ............. T. palpatus Parent, 1929

– Antenna distinctly black dorsally; other features various ............................................................... 25

25. Fore coxa with mainly white setae, with at most 2–3 black apical bristles; mid coxa with white setae and 1 black bristle; cerci dorsally adjoined, leaflike (Fig. 11G); body: 4.3 mm ................................ ........................................................................................................................ T. manambato sp. nov.

– Fore coxa with mainly black bristles and setae; mid coxa with black bristle and setae; cerci various.............................................................................................................................................. 26

26. Wing crossvein dm-m ⅔ as long as distal part of M 4; cercus gradually narrowed towards apex (Fig. 3E); body: 4–5 mm ............................................................................ T. capensis Curran, 1926

– Wing crossvein dm-m as long as distal part of M 4; cercus leaflike ................................................ 27

27. Antenna almost entirely black; palp black-brown on basal half; cerci dorsally widely separated, elongate-ovate, with narrow finger-like apex (Fig. 13F); body: 3.8 mm ( T. versutus group, in part) ................................................................................................................... T. cataractae sp. nov.

– Antenna black dorsally, yellow ventrally; palp entirely yellow; cerci dorsally adjoined, leaflike (Fig. 12F); body: 3.1 mm ...................................................................................... T. fluvialis sp. nov.

28. Fore coxa anteriorly and fore femur ventrally with mainly black hairs; hind femur poorly setose; cercus 1.5 × as long as tergite 5 (Fig. 3D); body: 6 mm .............................. T. virgatus Curran, 1926

– Fore coxa and femur with almost exclusively white hairs; hind femur with or without long setae; male cercus at most as long as tergite 5 .......................................................................................... 29

29. Hind femur with ventral rows of black setae, about 2 × as long as femur height (Fig. 2C); all tarsomeres annulate with black and white (Fig. 2A); body: 4–5 mm ............. T. calopus Loew, 1852

– Hind femur with ventral rows of short white hairs or glabrous; tarsi not annulate ........................ 30

30. All tarsi entirely black or brownish at base (Fig. 1A); surstylus straight, slightly narrowed distally (Fig. 1E); body: 2.5–3.3 mm ............................................................... T. argyropalpis Becker, 1910

– All tarsi mostly yellow, with last segments dark or dark at apices ( T. quadrisetus group, in part) 31

31. Mid femur with row of ventral setae on distal half, 2 × as long as femur height; tarsi gradually darkened towards tips (Fig. 15A); surstylus bilobate, with narrow lobes (Fig. 15F); cerci free, evenly broad to apex (Fig. 15E); body: 4 mm ........................................................... T. subpalpatus sp. nov.

– Mid femur with rows of ventral setae, half as long as femur height; tarsomere 5 of all tarsi deep black (Fig. 14D); tarsomeres 1–4 of fore and mid tarsi yellow (Fig. 14A); tarsomeres 1–4 of fore tarsus ventrally with silvery shine; surstylus one-lobed, widened distally (lateral view); cerci dorsally fused at base, free and narrow distally (Fig. 14G); body: 5.5 mm ............................. T. medvedevi sp. nov.