Bicellaria

Barták, Miroslav & Kubík, Štěpán, 2013, Species of Bicellaria Macquart (Diptera: Hybotidae) of Europe, with descriptions of four new species, Zootaxa 3647 (2), pp. 251-278 : 273-276

Key to species of Bicellaria of Europe

Remarks. Absolute measures given in the text (performed on dry mounted material) are only benchmarks: they may slightly differ in unusually small or large individuals. Only those setae on the palpus are counted which are longer than 0.05 mm (those occurring on the palpifer are not counted). Long setae on dorsal side of the third antennal segment may be broken or their presence/absence may be variable (we found a single specimen of B. subpilosa with long fine seta on the third antennal segment). Those setae on intrahumeral and posthumeral areas are counted which occur outside the single row of dorsocentrals in the presutural area. Prescutellar depression in some species contains differently long and more erect microtrichia giving this area lighter appearance in dorsal view, this area is mostly sharply delimited and this character state is referred in the text as follows: “prescutellar depression lighter than other parts of mesoscutum in dorsal view”. Nearly all characters sometimes vary (including precise shape of male hypandrial processes) which makes identification extremely difficult. Females are sometimes indistinguishable (most notably: B. italica - B. intermedia ), thus faunistic records should be based only on males and always be supported by dissection of the genitalia. Both B. albopilosa and B. spuria probably represent complexes of sibling species. For this reason, some recently published records should be considered carefully due to possible misidentifications (e.g. Raffone 2006, 2008; Jonassen 1984; Parvu 2003, 2005).

1 Antennal stylus together with slender portion of third segment half as long as broad basal portion of third segment ( Fig. 47 ); acrostichals and dorsocentrals (except last two pairs of dorsocentrals) very short (less than 0.05 mm long); all tibiae without any setae obviously longer than setulae; male hypandrial processes long setose along the whole inner margin; very small species (wing length 1.9 mm).................................................... B. dispar Oldenberg

- Antennal stylus together with slender portion of third segment at least as long as broad basal portion of third segment (as in Fig. 48 ); acrostichals and dorsocentrals longer than 0.05 mm; remaining characters disagree....................... 2

2 (1) Palpus with 4 or more black setae; third antennal segment with dorsal seta(e); all body setae black.................. 3

- Palpus with 1–3 black setae (rarely with an additional pale seta), if palpus with more than 4 setae ( B. andorra sp. nov.), then sides of abdomen with yellowish-white setae; third antennal segment with or without dorsal seta(e)............. 6

3 (2) Mesoscutum with two pale (silvery) stripes between rows of acrostichals and dorsocentrals apparent from both dorsal and caudal views (in female covering most of mesoscutum); usually less than 9 setae outside rows of dorsocentrals at presutural area; abdomen light bluish grey in lateral view; male genitalia as in Figures 3–4 ( B. pilosa complex-part).............................................................................................. B. alpina Bezzi

- Mesoscutum uniformly dark velvety black without any stripes; usually 10 or more setae outside rows of dorsocentrals at presutural area; abdomen dark greyish to blackish brown in lateral view....................................... 4

4 (3) Third antennal segment usually with 4 or more dorsal setae, second segment with curiously long lateral setae pointing forwards; fore tibia with posteroventral setae shorter than diameter of tibia and with a row of 4–6 erect posterodorsal setae about 4X longer than diameter of tibia (0.25 mm long); hind tibia broadly thickened on apical third in male and slender in female; male hypandrium with short and broad processes bearing long apical seta, two phallic hooks present, phallus strongly sclerotized, forming flat and long valve-like structure ( Figs 19–20 )................... B. longisetosa Chvála

- Third antennal segment usually with 1–3 dorsal setae, second segment with short lateral setae (but with long ventral setae); fore tibia differently setose; hind tibia more evenly dilated in both sexes; male hypandrial processes without long apical seta, three phallic hooks (left hook bifurcate), phallus membranous, not forming valve-like structure. ( B. pilosa complexpart)............................................................................................ 5

5 (4) Face narrow (about 5–6 facets combined), almost parallel throughout (0.06–0.07 mm); about 10 setae on posthumeral and intahumeral areas; male hypandrial processes broadened near apex, left phallic hook bifurcate, its anterior arm bent, postgonites strongly asymmetrical, right one with ventral extension ( Figs 29–30 ).................. B. setipalpus sp. nov.

- Face broad (about 8–9 facets combined), in lower half even broader (0.11 mm) than in upper half (0.10 mm); usually more than 10 setae on posthumeral and intrahumeral areas; male hypandrial processes apically narrow; left phallic hook bifurcate, its anterior arm straight ( Figs 27–28 ).............................................. B. pilosa Lundbeck

6 (2) Hind basitarsus (and usually also the hind tarsomeres 2) distinctly swollen (usually more than 2.3X broader than hind tarsomere 3 and usually broader than 0.10 mm); additional characters: fore tibia with ventral pilosity on apical third at most slightly shorter than on fore basitarsus and posteroventral setae short, at most as long as pilosity and usually shorter than depth of tibia (as in Fig. 46 ), face very narrow (less than 3 facets combined, less than 0.03 mm at narrowest point), abdomen at least partly pale setose (exception: male B. nigrita ), third antennal segment without dorsal seta(e), hypandrial processes never strikingly shortened ( B. nigra complex)...................................................... 7

- Hind basitarsus slender (usually less than 2.0X broader than hind tarsomere 3 and usually narrower than 0.10 mm); additional characters in different combinations.............................................................. 9

7 (6) Third antennal segment arched dorsally; mid tibia usually without dorsal setae differentiated from short hairs; hind femur shorter than 1.2 mm; hind tibia dilated in basal third; male: postgonites shortened (about 0.10 mm long), both phallic hooks present, long and strong, longer than postgonites, right one slightly shorter and narrower than left one ( Fig. 25 ), squamae mostly with dark fringes................................................................ B. nigrita Collin

-. Third antennal segment nearly straight dorsally; mid tibia with 1–3 outstanding dorsal setae, about twice as long as short hairs on limb; hind femur longer than 1.3 mm; hind tibia equally slender in basal third; male: postgonites not reduced (slightly shortened in B. halterata ), phallic hooks different, squamae mostly with pale fringes...................... 8

8 (7) All large setae on mesoscutum black; male: halter usually dark, postgonites long (more than twice as long as broad), left phallic hook long, without lateral process, right one strongly reduced ( Fig. 23 ); female: broad portion of third antennal segment usually longer than 0.15 mm, lustrous portions of abdominal tergites 6–7 comprise about basal third of these tergites................................................................................... B. nigra (Meigen)

- Large setae on mesoscutum mostly white to brownish-yellow (at least scutellars, last pair of dorsocentrals and notopleurals); male: halter yellow, postgonites shorter (about 1.5X as long as broad), both phallic hooks long, left one with lateral process (best visible from below, Fig. 11 ); female: broad portion of third antennal segment usually shorter than 0.14 mm, lustrous portions of abdominal tergites 6–7 comprise more than basal half of these tergites......... B. halterata Collin

9 (6) Third antennal segment with one to several long dorsal setae; male with two phallic hooks (both exceeding postgonites) ( B. austriaca complex)................................................................................ 10

- Third antennal segment without long dorsal setae; male with 1–2 phallic hooks................................ 16

10 (9) Male........................................................................................... 11

- Female......................................................................................... 14

11 (10) Prescutellar depression lighter than other parts of mesoscutum in dorsal view (lighter area reaches hind acrostichals); halter yellow; hypandrial processes swollen apically, bearing several rather long setae on apex, both phallic hooks almost equally long, right one more sharply bent ( Figs 15–16 ).............................................. B. italica sp. nov.

- Prescutellar depression usually evenly dark in dorsal view (rarely lighter in a narrow area not reaching halfway between scutellum and hind acrostichals); halter dark brown to yellowish brown; remaining characters disagree............. 12

12 (11) Face parallel-sided or slightly broadened ventrally (about 5 facets combined, 0.06 mm broad at narrowest point); hypan-

drial processes short (0.09–0.10 mm) and broadly U-shaped (distance between their inner margins of processes about 0.04– 0.05 mm), both phallic hooks equally long and equally bent ( Figs 9–10 )...................... B. collini Tuomikoski - Face narrowing ventrally (about 3 facets combined, 0.04 mm broad at narrowest point); hypandrial processes longer and narrowly U-shaped (distance between inner margins of processes about 0.02–0.03 mm), phallic hooks different...... 13

13 (12) Usually more than 9 setae in posthumeral and intrahumeral areas; hypandrial processes broader, with several rather long setae near apex, phallic hooks unequal, shorter and broader ( Figs 7–8 ).................... B. austriaca Tuomikoski

- Usually less than 7 setae in posthumeral and intrahumeral areas; hypandrial processes narrower, with at most a single longer seta on apex, other setae much shorter, long and narrow phallic hooks nearly equal in length ( Figs 13–14 )....................................................................................... B. intermedia Lundbeck

14 (10) Face parallel-sided or slightly broadening ventrally (about 5 facets combined, 0.06 mm broad at narrowest point); abdominal tergites 6–7 broadly lustrous on basal half or more.................................... B. collini Tuomikoski

- Face narrowed ventrally (about 3 facets combined, 0.04 mm broad at narrowest point); abdominal tergites 6–7 nearly completely microtrichose.............................................................................. 15

15 (14) Halter brown; usually more than 9 setae in posthumeral and intrahumeral areas............. B. austriaca Tuomikoski

- Halter yellow; usually less than 9 setae in posthumeral and intrahumeral areas................................................................................................. B. intermedia Lundbeck, B. italica sp. nov.

16 (9) Fore tibia with ventral pilosity on apical third at most slightly shorter than pilosity on fore basitarsus and/or posteroventral setae on apical third of tibia shorter than depth of tibia (as in Fig. 46 , observe in exactly posterior view)............ 17

- Fore tibia with ventral pilosity on apical third at most one-third as long as on fore basitarsus and posteroventral setae on apical third of tibia at least twice as long as pilosity, and usually longer than depth of tibia (as in Fig. 45 )............ 20

17 (16) Hind tibia slender throughout; lower occipital setae mostly pale; male: hypandrial processes short and broad, right phallic hook long, simply curved and exceeding postgonites, left one slightly shorter, triangular in shape ( Figs 31–32 ).................................................................................... B. simplicipes (Zetterstedt)

- Hind tibia distinctly swollen apically (less so in female); lower occipital setae black; male: hypandrial processes not conspicuously short and broad, right phallic hook strongly reduced or absent, left one long and simply curved ( B. sulcata complex)........................................................................................... 18

18 (17) Abdomen with long white setae on sides; the anteromost acrostichals and dorsocentrals subequally long as those just before suture (first three about 0.15 mm long or even longer in males); hind femur without posteroventral setae................................................................................................ B. andorra sp. nov.

- Abdomen entirely black setose; the anteromost acrostichals and dorsocentrals distinctly shorter than those just before suture (first three about 0.09 mm long); hind femur with posteroventral setae (if abdomen partly pale setose, compare B. halterata )....................................................................................... 19

19 (18) Face very narrow (less than 2 facets combined, 0.02 mm), narrowed ventrally; male presutural area evenly dark in dorsal view (male) or with pale spot sharply triangular-shaped (female); hind tibia more equally swollen towards tip, at its broadest point subequally broad as hind femur even in male (both 0.12–0.13 mm); male hypandrial processes slender; apical corner of postgonites broadly rounded ( Figs 43–44 ).............................................. B. vana Collin

- Face broader (about 3 facets combined, 0.03 mm), parallel-sided; presutural area lighter in dorsal view than remaining parts of mesoscutum in both sexes, of rectangular to semicircular appearance; hind tibia strongly swollen towards tip (usually more than 0.15 mm at broadest point in male and some 0.14 mm in female), at its broadest point broader than hind femur (0.12 mm); male hypandrial processes broader; apical corner of postgonites narrower and more pronounced ( Figs 39–40 )........................................................................ B. sulcata (Zetterstedt)

20 (16) Abdomen partly pale setose (at least on sides of tergite 2)................................................. 21

- Abdomen entirely black setose....................................................................... 22

21 (20) Legs microtrichose, with longer and slender tarsi (combined length of fore+mid+hind basitarsus usually more than 1.3 mm); usually less than 7 setae in posthumeral and intrahumeral areas; male hind tibia gradually slightly swollen, lateral parts of abdomen brown; hypandrial processes shorter (0.11 mm), both phallic hooks narrow, connected ventrally ( Figs 1– 2 ); female tergites 6–8 at least partly microtrichose...................................... B. albopilosa Chvála

- Legs lustrous, with shorter tarsi (combined length of fore+mid+hind basitarsus usually less than 1.2 mm); usually more than 8 setae in posthumeral and intrahumeral areas; male hind tibia strongly and abruptly swollen, lateral parts of abdomen pale and almost silvery grey; hypandrial processes long (0.15 mm), both phallic hooks present, left one hoe-like broadened laterally (best visible from behind) ( Figs 35–36 ); female tergites 6–8 almost entirely lustrous.................................................................................................. B. stackelbergi Tuomikoski

22 (20) Halter yellow; male hypandrium large with contrastingly short, narrow, broadly U-shaped and long setose processes ( Fig. 18 ); female tergites 5–8 almost entirely lustrous......................................... B. kocoureki sp. nov.

- Halter brownish yellow to black; male hypandrium different; female tergites 5–8 at least partly microtrichose........ 23

23 (22) Male........................................................................................... 24

- Female......................................................................................... 27

24 (23) Postgonites slightly broadened laterally and narrow in lateral view, hypandrium with short (0.06–0.09 mm) and broad processes (3– 4 X as long as broad), two equally shaped and long phallic hooks ( Figs 41–42 )........... B. uvens Melander

- Postgonites not broadened laterally and trapezoid in lateral view, hypandrium with narrower and longer processes, a single long phallic hook present (the other less than one-quarter as long)........................................... 25

25 (24) Face broad in ventral portion (usually more than 5 facets combined, 0.06 mm); mid femur with complete row of anteroventrals at least half as long as depth of femur at mid-length; hind tibia with ventral setae about twice as long as depth of tibia; prescutellar depression paler than remaining parts of mesoscutum in dorsal view; phallic hook bent in S-shaped ( Fig. 37 ).

.................................................................................. B. subpilosa Collin - Face narrow in ventral portion (less than 4 facets combined, 0.04 mm); mid femur with anteroventrals shorter than half of femur depths at mid-length; hind tibia with ventral setae at most slightly longer than tibia depth of tibia; prescutellar depression paler or evenly dark as remaining parts of mesoscutum in dorsal view; phallic hook simply bowed ( Figs 33 , 21 )................................................................................................ 26 26 (25) Hypandrium with rather long (0.13 mm), slender and straight processes ( Fig. 34 ).................. B. spuria (Fallén)

- Hypandrium with rather short (0.09–0.11 mm), apically foot-like bent and broadened processes ( Fig. 22 ).. B. mera Collin

27 (23) Face broad in ventral part (usually broader than 0.05 mm, more than 4 facets combined); mid femur with complete row of anteroventrals at least half as long as depth of femur at mid-length; hind tibia with ventral setae about twice as long as depth of tibia; prescutellar depression paler than remaining parts of mesoscutum in dorsal view..... B. subpilosa Collin

- Face narrower in ventral part (usually less than 0.04 mm, about 3 facets combined); mid femur with anteroventrals shorter than one-third of femur depth at mid-length; hind tibia with ventral setae at most slightly longer than depth of tibia; prescutellar depression paler than remaining parts of mesoscutum in dorsal view or evenly dark...................... 28

28 (27) Usually two dorsal setae on fore trochanter; usually more than 9 setae in posthumeral and intrahumeral areas; hind tibia swollen (usually about 0.13 mm at broadest point)......................................... B. uvens Melander

- Usually a single seta on fore trochanter; usually less than 9 setae in posthumeral and intrahumeral areas; hind tibia less swollen (usually less than 0.12 mm at broadest point).................................................... 29

29 (28) Tergite 8 at least in basal half lustrous.................................................... B. spuria (Fallén)

- Tergite 8 almost entirely microtrichose...................................................... B. mera Collin

Figures

FIGURES 41 – 48. 41 – 44. Hypandrium (ventral view) and phallus with postgonites (lateral view). 41 – 42. Bicellaria uvens Melander. 43 – 44. Bicellaria vana Collin. 45 – 46. Distal part of front tibia and proximal part of front basitarsus (posterior view). 45. Bicellaria spuria (Fallén). 46. Bicellaria vana Collin. 47 – 48. Antennae. 47. Bicellaria dispar Oldenberg. 48. Bicellaria alpina Bezzi (microchaetae mostly omitted). Scale bars = 0.10 mm.

FIGURES 1 – 8. Hypandrium (ventral view) and phallus with postgonites (lateral view). 1 – 2. Bicellaria albopilosa Chvála. 3 – 4. Bicellaria alpina Bezzi. 5 – 6. Bicellaria andorra sp. nov. 7 – 8. Bicellaria austriaca Tuomikoski. Abbreviations: eapejaculatory apodeme, hph—phallic hooks, mep—median extensions of postgonites, pgn—postgonites, vap—ventral apodeme. Scale bars = 0.10 mm.

FIGURES 17 – 24. Hypandrium (ventral view) and phallus with postgonites (lateral view). 17 – 18. Bicellaria kocoureki sp. nov. 19 – 20. Bicellaria longisetosa Chvála. 21 – 22. Bicellaria mera Collin. 23 – 24. Bicellaria nigra (Meigen). Scale bars = 0.10 mm.

FIGURES 25 – 32. Hypandrium (ventral view) and phallus with postgonites (lateral view). 25 – 26. Bicellaria nigrita Collin. 27 – 28. Bicellaria pilosa Lundbeck. 29 – 30. Bicellaria setipalpus sp. nov. 31 – 32. Bicellaria simplicipes (Zetterstedt). Scale bars = 0.10 mm.

FIGURES 9 – 16. Hypandrium (ventral view) and phallus with postgonites (lateral view). 9 – 10. Bicellaria collini Tuomikoski. 11 – 12. Bicellaria halterata Collin. 13 – 14. Bicellaria intermedia Lundbeck. 15 – 16. Bicellaria italica sp. nov. Scale bars = 0.10 mm.

FIGURES 33 – 40. Hypandrium (ventral view) and phallus with postgonites (lateral view). 33 – 34. Bicellaria spuria (Fallén). 35 – 36. Bicellaria stackelbergi Tuomikoski. 37 – 38. Bicellaria subpilosa Collin. 39 – 40. Bicellaria sulcata (Zetterstedt). Scale bars = 0.10 mm.