Stenopogoninae

Londt, Jason G. H., 2013, A remarkable new genus of robber flies, Akatiomyia gen. n., from the Western Cape Province of South Africa, and a new key to the genera of Afrotropical Stenopogoninae (Diptera: Asilidae), African Invertebrates 54 (1), pp. 57-57 : 62-66

Key to genera of Afrotropical Stenopogoninae

This key has been developed from that published originally by Londt (1999) in order to accommodate Oligopogon and genera described after 1999 . The number of currently recognized species, and references to the most recent taxonomic literature relating to species is provided after generic names.

1 Anatergites setose...................................................................................................2

– Anatergites asetose...............................................................................................10

2 Postpedicel tipped with a small apical pit enclosing a ‘seta-like’ sensory element (remains of a style).................................................................................................9

– Postpedicel bearing a distinct style made up of 2 or 3 elements (including a terminal ‘seta-like’ sensory element); abdominal T1–4 with a group of strong dorsolateral macrosetae..............................................................................................................3

3 Occiput with obvious macrosetae..........................................................................5

– Occiput lacking macrosetae (i.e. with weak setae only)........................................4

4 Eye:face width ratio <1.1:1; scape clearly longer than pedicel; hypandrium less than half as long as epandrial lobes ......................................................................... ......................................................... Dioctobroma Hull, 1962 (1 sp., Londt 1983)

– Eye:face width ratio>1.3:1; scape and pedicel about equal in length; hypandrium about as long as epandrial lobes........ Dogonia Oldroyd, 1970 (1 sp., Londt 2008)

5 Proepisternum with a few strong macrosetae as well as fine setae; pronotal and mesonotal macrosetae very strong (flies have bristly appearance).......................... ........................................ Anasillomos Londt, 1983 (1 sp., Dikow & Londt 2000)

– Proepisternum with fine setae only (some may be stronger than others, but never as strong as mesonotal macrosetae).......................................................................6

6 Abdominal T1–4 with group of strong macrosetae dorsolaterally; antennal style consists of 2 elements (1 small basal segment and a ‘seta-like’ sensory element); ♂ genitalia bulbous; ♀ T7 and T8 of nearly equal length........................................ ............................ Ontomyia Dikow & Londt, 2000 (1 sp., Dikow & Londt 2000)

– Only abdominal T1 with group of strong macrosetae dorsolaterally; antennal style consists of 3 elements (2 basal segments and a ‘seta-like’ sensory element); ♂ genitalia slender, never bulbous; ♀ T8 distinctly shorter than T7 ( Fishermyia ♀ unknown)...............................................................................................................7

7 Facial swelling pronounced in lower and upper regions.......................................... .................................. Oratostylum Ricardo, 1925 (3 spp., Dikow & Londt 2000)

– Facial swelling weak, only lower margin moderately pronounced........................8

8 Two or more pairs of apical scutellar macrosetae; mystax occupying almost entire face although sometimes weak in dorsal part; antennal postpedicel usually somewhat clavate, <1.5× longer than scape and pedicel combined (southern Africa) ............. ..................................... Remotomyia Londt, 1983 (4 spp., Dikow & Londt 2000)

– A single pair of apical scutellar macrosetae; mystax occupying ventral ⅓ of face only, dorsal part asetose; antennal postpedicel elongate, spindle shaped,>1.5× longer than scape and pedicel combined ( Madagascar)........................................... ........................................................ Fishermyia Londt, 2012 (1 sp., Londt 2012 b)

9 Facial swelling occupying about ¾ of face and entirely covered with macrosetae and setae; presutural dorsocentral setae well developed; vein M 1 not strongly arched anteriorly; postmetacoxal membrane covered with long setae ................................ ................................................ Daspletis Loew, 1858 (8 spp., Londt 1983, 2010 a)

– Facial swelling occupying at most ½ of face and often with macrosetae only on lower half; dorsocentral setae present only on posterior half of mesonotum; vein M 1 usually strongly arched anteriorly; postmetacoxal membrane usually asetose ............................................ Microstylum Loew, 1838 (79 spp., requires revision)

10 Anal lobe and alula without bordering vein (i.e. costa terminates at or before point where anal vein joins wing margin) .....................................................................11

– Costa extends around entire wing margin (i.e. borders anal lobe and alula; weakly in Trichoura )........................................................................................................21

11 Pulvilli minute or absent......................................................................................12

– Pulvilli well developed.........................................................................................16

12 Abdomen broad and dorsoventrally compressed (width:length ratio of T2>2)...13

– Abdomen cylindrical. Not obviously dorsoventrally compressed (width:length ratio of T2<1.5).......................................................................................................15

13 Costal vein extending around wing tip, terminating at point where CuA 2 and A 1 reach wing margin; cells r 5 and m 3 open at wing margin.....................................14

– Costal vein falling short of juncture of CuA 2 and A 1; cells r 5 and m 3 stalked, stalks frequently failing to reach wing margin................................................................... .................................................. Sisyrnodytes Loew, 1856 (15 spp., Londt 2009 a)

14 Cell m 3 open; vein R 4 usually with basal stump-vein; pulvilli poorly developed, but clearly discernable; hypandrium somewhat flat or only gently concave ................. ............................................... Acnephalomyia Londt, 2010 (7 spp., Londt 2010 c)

– Cell m 3 closed and stalked; vein R 4 lacking basal stump-vein; pulvilli minute and difficult to detect; hypandrium distinctly cup-shaped.............................................. ...................................................... Astiptomyia Londt, 2010 (1 sp., Londt 2010 c)

15 Small flies (wing length <3.5 mm); empodia apparently absent; vein R 4 lacking basal stump-vein; macrosetae of mesonotum greatly developed, many times longer than accompanying setae ........ Ammodaimon Londt, 1985 (2 spp., Londt 2010 c)

– Larger flies (wing length>6.0 mm); empodia well developed; vein R 4 with basal stump-vein; macrosetae of mesonotum moderately developed, not many times longer than accompanying setae .............................................................................. ............................................... Sporadothrix Hermann, 1907 (1 sp., Londt 2010 c)

16 Postmetacoxal sclerotized bridge present ................................................................ .................................................. Rhabdogaster Loew, 1858 (38 spp., Londt 2006)

– Postmetacoxal area membranous.........................................................................17

17 Antennal style with long loosely arranged setae; prosternum large, abutting proepisternum and prothoracic coxae; alula highly reduced.............................................. ................................. Oligopogon Loew, 1847 (11 spp., requires modern revision) Note: See discussion below on the inclusion of this genus in the subfamily.

– Antennal style lacking long setae; prosternum small, disassociated from proepisternum and prothoracic coxae; alula moderately well developed......................18

18 Mesonotum greatly elevated anteriorly and hump-like ........................................... ...................................................... Oxynoton Janssens, 1951 (2 spp., Londt 1996)

– Mesonotum not hump-like, but of more usual form............................................19

19 Antennal style apparently robust, broader than postpedicel, covered with numerous, short, tightly-packed setae........................... Akatiomyia gen. n. (1 sp., this paper)

– Antennal style slender, asetose.............................................................................20

20 Metacoxae with elongate, distally rounded, peg-like process on anterior surface... ........................................................ Ischiolobos Londt, 2005 (4 spp., Londt 2005)

– Metacoxae lacking peg-like process on anterior surface ......................................... ............................................... Afroholopogon Londt, 1994 (18 spp., Londt 2005)

21 Palpi 1-segmented................................................................................................22

– Palpi 2-segmented................................................................................................24 Note: Palpi are not always easy to study. One­segmented palpi are usually fairly robust and curved, such that their distal ends converge. Two­segmented palpi may have weak distal parts that are tucked away below epistomal margin.

22 Proboscis with spine-like processes distally; antennal style not clearly differentiated, distal seta-like sensory element sub-terminally situated.......................................... .................................. Hynirhynchus Lindner, 1955 (2 spp., Londt 1992 a, 2010 b)

– Proboscis of more usual form and lacking spine-like processes distally; antennal style clearly defined with terminal pit-enclosed seta-like sensory element.........23

23 Proboscis shorter than antenna; mystax covering ventral third of face; ♂ mesotarsomeres 4 and 5 with highly modified, rather spade-shaped setae (usually reddish) ....................................................... Habropogon Loew, 1847 (8 spp., Londt 2000)

– Proboscis longer than antenna; mystax covering ventral half of face; ♂ mesotarsomeres 4 and 5 with normally shaped setae............................................................... ....................................................... Pycnomerinx Hull, 1962 (3 spp., Londt 1990)

24 Head almost circular in anterior view (i.e. face narrow).....................................25

– Head clearly wider than high in anterior view.....................................................29

25 Katatergites bare...................................................................................................26

– Katatergites setose................................................................................................27

26 Prothoracic femur with large, proximoventral spinose process (i.e. strongly raptorial).......................................... Gonioscelis Schiner, 1866 (38 spp., Londt 2004)

– Prothoracic femur of more usual form and lacking large spinose process .............. ........................................................ Stenopogon Loew, 1847 (2 spp., Londt 1999)

27 Dorsocentral macrosetae extend along entire length of mesonotum ....................... ............................................................ Haroldia Londt, 1999 (2 spp., Londt 1999)

– Dorsocentral macrosetae confined to posterior region of mesonotum.................28

28 Antennal style composed of 2 elements (cylindrical segment-like element and terminal spine-like element); ♂ hypandrium usually bifurcate distally................... ............................................... Afroscleropogon Londt, 1999 (7 spp., Londt 1999)

– Antennal style composed of 3 elements (narrow basal segment-like element, cylindrical segment-like element and terminal spine-like element); ♂ hypandrium usually simple ..................... Rhacholaemus Hermann, 1907 (9 spp., Londt 1999)

29 Proboscis strongly downward-curved, resembling a parrot’s beak.......................... ......................................... Ancylorhynchus Berthold, 1827 (29 spp., Londt 2011)

– Proboscis of more usual form, not strongly down-curved...................................30

30 Face strongly projecting ventrally (not dorsally), giving a pointed, nose-like appearance in profile; mystacal macrosetae largely confined to small area at apex of pointed gibbosity................. Lycostommyia Oldroyd, 1980 (6 spp., Londt 1992 a)

– Face not projecting ventrally and of more usual form.........................................31

31 Mystax extends from antennal bases to epistomal margin (i.e. entire profile)....32 Note: Pedomyia astroptica keys out here, but has characteristic antennal structure.

– Mystax less extensive, there being a clearly visible gap between antennal sockets and dorsal mystacal setae.....................................................................................36

32 Antenna with compressed, strap-like postpedicel and terminal 2-segmented style of similar form .................... Hermannomyia Oldroyd, 1962 (2 spp., Londt 1981)

– Antenna of different form....................................................................................33

33 Large flies (wing length> 15 mm); palpi well developed; anepimeral macroseta absent ....................................................... Bana Londt, 1992 (2 spp., Londt 2013)

– Small flies (wing length <10 mm); palpi moderately developed; anepimeral macroseta usually present...........................................................................................34

34 ♂ terminalia club-like; epandrium greatly developed, hemispherical; hypandrium greatly reduced................................. Corymyia Londt, 1994 (4 spp., Londt 1994)

– ♂ terminalia of more usual form; epandrium not greatly developed; hypandrium not greatly reduced...............................................................................................35

35 ♂ gonocoxite with 2 subequal pointed distal processes, the outer one with at most a small tumid dorsodistal projection; mystax well developed, extending to antennal sockets; scutellum with many apical setae that usually extend weakly onto the disc (central area usually asetose) ....... Connomyia Londt, 1992 (20 spp., Londt 1993)

– ♂ gonocoxite with outer process having a distal or dorsodistal flange-like process; mystax moderately well developed, extending to antennal sockets, but usually weak in upper part; scutellum usually with few apical setae that rarely extend onto disc .......................................................... Danomyia Londt, 1993 (9 spp., Londt 1993)

36 Anepimeral macroseta present; metathoracic empodia laterally compressed and blade-like................................ Empodiodes Oldroyd, 1972 (4 spp., Londt 2012 a)

– Anepimeral macroseta absent; metathoracic empodia seta-like, not laterally compressed and blade-like..........................................................................................37

37 Lower ¾ of face strongly gibbose, upper part of swollen area clearly defined...38

– Face at most gently gibbose, upper part of swollen area not clearly defined......39

38 Body entirely metallic blue-black; postpedicel elongate, cylindrical, about twice as long as first two segments combined; wing uniformly blackish.......................... ................................................ Teratopomyia Oldroyd, 1980 (1 sp., Londt 2009 b)

– Body not entirely metallic blue-black; postpedicel strongly club-shaped, about as long as first two segments combined; wing largely transparent with dark spots (especially a ‘stigma-like’ marking at base of cell r 1) .............................................. ........................................................ Hypenetes Loew, 1858 (21 spp., Londt 1985)

39 Mystax occupies at most the lower one-third of face..........................................40

– Mystax occupies at least the lower half of face...................................................44

40 Wing cells m 3 and cup closed and stalked; ♂ hypandrium reduced and largely fused with gonocoxites .............................. Trichoura Londt, 1994 (6 spp., Londt 1994)

– Wing cells m 3 and cup open at wing margin (even if only narrowly); ♂ hypandrium moderately well developed and not fused with gonocoxites...............................41

41 Epandrial lobes almost entirely separated (joined proximally)...........................42

– Epandrial lobes fused for at least proximal half of length...................................43

42 Small (wing length <3 mm) ....... Microphontes Londt, 1994 (3 spp., Londt 1994)

– Larger (wing length> 5 mm)..... Antiscylaticus Londt, 2010 (1 sp., Londt 2010 b)

43 Scutellar disc lacking setae; epandrial lobes fused for about half of length............ ......................................................... Macroetra Londt, 1994 (3 spp., Londt 1994)

– Scutellar disc with few (c. 4) setae; epandrium with slight distal indentation, otherwise fused for entire length........... Irwinomyia Londt, 1994 (2 spp., Londt 1994)

44 Antennal postpedicel widening toward the middle (in lateral view), apical half appearing strongly ventrally incised; mystax occupies about ¾ of face ..................... .......................................................... Pedomyia Londt, 1994 (9 spp., Londt 1994)

– Antennal postpedicel spindle-shaped; mystax occupies about ½ of face............45

45 ♂ epandrial lobes long, entirely separated or very narrowly joined proximally; hypandrium more or less straight and distally directed ............................................... ....................................................... Scylaticus Loew, 1858 (35 spp., Londt 1992 b)

– ♂ epandrial lobes short, fused proximally for about ⅓ their length; hypandrium elongate, ventrally directed with upturned distal region.......................................... ....................................................... Agrostomyia Londt, 1994 (1 sp., Londt 1994)