Platypalpus

Kustov, Semen, Shamshev, Igor & Grootaert, Patrick, 2015, New data on the genus Platypalpus (Diptera: Hybotidae) from the Caucasus with description of seven new species, Zootaxa 3973 (3), pp. 451-473 : 468-471

Key to species of Platypalpus from the Caucasus

The following key includes all species of Platypalpus recorded currently from the Caucasus, adapted with some modifications after Chvála (1989) and Grootaert & Chvála (1992). It is evident that many species of Platypalpus remain unknown from the Caucasus. So, the main purpose of our key is to provide rather rapid identification, the result of which should be checked in doubtful cases using keys and diagnoses given in the noted papers.

1 Y ellow species; thorax yellow in ground-colour, at least pleura yellow........................................... 2

- Black species; thorax black in ground-colour even if densely light grey dusted (abdomen rarely yellow)............... 6

2 (1) No distinct vertical bristles, vertex and upper part of occiput with numerous subequal hair-like setae. Mesonotum extensively polished; no humeral bristle. At most very small apical spur on mid tibiae....................................... 3

- 1 or 2 pairs of distinct vertical bristles, which, even if small, are distinctly longer than other pubescence. Mesonotum almost bare or polished; humeral bristle absent or present. Apical spur on mid tibia present or absent........................ 4

3 (2) Acrostichals and dorsocentrals undifferentiated, scutum evenly and densely covered with small hair-like setae, with dark median stripe. Mid tibia with coating of whitish pile at tip only. Antenna black, postpedicel about twice as long as wide, stylus rather short, about twice as long as postpedicel. Mid femur slightly swollen, with ventral spines in posterior row longer and thinner, and almost equally long towards tip................................................ P. pectoralis (Fallén)

- Acrostichals clearly separated from dorsocentrals, irregularly 2–4-serial; mesonotum usually almost entirely black (sometimes with dark median stripe or in very pale specimens almost yellow). Mid tibia with coating of whitish pile on apical half. Antenna with scape and pedicel yellow, postpedicel blackish, nearly as long as wide, stylus much longer. Mid femur rather evenly slender, with ventral spines of subequal length becoming gradually shorter towards apex.......... P. mi k i i (Becker)

4 (2) 1 pair of distinct vertical bristles. Occiput black. Mesonotum with acrostichals biserial............................. 5

- 2 pairs of distinct vertical bristles, inner convergent, outer divergent. Occiput yellow. Mesonotum with acrostichals 10–12- serial, narrowly separated by bare area from dorsocentrals.................................... P. pallescens Kovalev

5 (4) Mid femur without posteroventral bristles behind rows of ventral spines. Mid tibia with slender yellow spur about as long as width of tibia.......................................................................... P. exilis (Meigen)

- Mid femur with distinct pale posteroventral bristles behind rows of ventral spines. Mid tibia with strong black spur distinctly longer than width of tibia................................................................ P. luteolus (Collin)

6 (1) No distinct vertical bristles, vertex and upper part of occiput with numerous long hair-like setae (in doubtful cases, species with thoracic hairs evenly distributed over mesonotum belong here)................................................ 7

- 1 or 2 pairs of distinct vertical bristles, which, even if small, are distinct from other pubescence...................... 9

7 (6) Mid femur without posteroventral bristles behind double row of spines. Acrostichals at most 4-serial, broadly separated from dorsocentrals by bare area. Male: fore and mid tarsomere 5 unmodified......................................... 8

- Mid femur with more or less distinct posteroventral bristles behind double row of spines. Acrostichals and dorsocentrals undifferentiated, scutum evenly covered with short hair-like setae. Male: fore and mid tarsomere 5 very long, the former nearly as long as fore tarsomeres 1–4 combined, the latter as long as mid tarsomeres 2–4 combined.............................................................................................. P. negrobovi Grootaert, Kustov & Shamshev

8 (7) Acrostichals numerous, irregularly 4-serial; dorsocentrals uniserial, flanked by numerous similar setae on supra-alar area. Pleura dusted except for polished katepisternum. Frons dusted. Antenna with postpedicel very short, hardly longer than broad. Mid tibia with coating of whitish pile on about apical half. Abdomen covered with scattered hair-like setae. Male: genitalia very large, globose...................................................................... P. ciliaris (Fallén)

- Mesonotum almost bare, acrostichals and dorsocentrals (including similar setae on supra-alar area) scattered and very minute. Pleura largely polished. Frons polished. Mid tibia without coating of whitish pile. Male: antenna with postpedicel 3– 4 X as long as wide; abdomen with dense hair-like setae; genitalia small. Female: postpedicel 2– 3 X as long as wide............................................................................................... P. stigmatellus (Zetterstedt)

9 (6) 1 pair of distinct vertical bristles....................................................................... 10

- 2 pairs of distinct vertical bristles, inner convergent, outer divergent........................................... 37

10 (9) Mesonotum more or less polished black, or subshining, very slightly and uniformly dusted (in doubtful cases postpronotal bristle absent or very short, stylus white or proepisternum with polished projection)................................. 11

- Mesonotum densely grey to light grey dusted (care must be taken with rubbed specimens), antennal stylus always black, postpronotal bristle always long, and no lustrous projection on proepisternum....................................... 18

11 (10) Mid tibia without apical spur........................................................................... 12

- Mid tibia with large, sharply pointed apical spur, which is at least as long as width of tibia (if in doubt, posteroventral bristles on mid femur present and stylus dark)................................................................... 16

12 (11) Antenna with stylus entirely black. Mid femur without posteroventral bristles (see couplet 7).......................................................................................... P. negrobovi Grootaert, Kustov & Shamshev

- Antenna with white stylus. Mid femur with long posteroventral bristles........................................ 13

13 (12) Fore femur with row of long posteroventral bristles. Postpronotal lobe very weakly developed; thoracic pleura extensively polished............................................................................................. 14

- Fore femur without posteroventral bristles behind double row of ventral bristly hairs. Postpronotal lobe more distinct and pleura densely grey dusted except for polished patch on katepisternum......................................... 15

14 (13) Ocellar bristles about as long as vertical bristles. Male: left cercus very large, with bent tip........... P. s mi r no v i Kovalev

- Ocellar bristles about two-thirds length of verticals. Male: tip of left cercus pointed.................. P. albiseta (Panzer)

15 (13) Mesonotum entirely dusted. Male: left epandrial lamella with ordinary bristles at tip............... P. pallidiseta Kovalev

- Mesonotum shiny. Male: left epandrial lamella with small black spines at tip....................... P. c a r o l i Grootaert

16 (11) Mesonotum very thinly greyish dusted, usually with median shiny stripe. Fore tibia with rim-like projection at tip beneath....................................................................................... P. mi nut us (Meigen)

- Mesonotum polished black, at least on posterior half in front of scutellum. Fore tibia without slight rim-like projection at tip beneath........................................................................................... 17

17 (16) Postpedicel about 1.5X as long as wide, brownish except for yellowish base. Mid femur with black ventral spines......................................................................................... P. pseudociliaris (Strobl)

- Postpedicel about twice as long as wide, almost entirely yellow. Mid femur with bicoloured ventral spines, which are black in apical part of femur and yellow closer towards base...................................... P. ruficornis (von Rosen)

18 (10) Antenna black, basal segments rarely somewhat brown or reddish-brown....................................... 19

- At least basal antennal segments yellow to yellowish-brown, or antenna entirely yellow............................ 26

19 (18) Apical spur on mid tibia very small, shorter than width of tibia; if about as wide as tibia ( P. cothurnatus ), with tiny curved hairs at tip (male) or blunt-tipped (female).................................................................... 20

- Mid tibia with large, sharply pointed apical spur, distinctly longer than width of tibia............................. 21

20 (19) Dorsocentrals only 3–5 in row, strong, long, much longer than acrostichals. Tarsi of all legs with distinct dark annulations; mid tibia with very small, blunt apical spur in both sexes........................................ P. cryptospina (Frey)

- Dorsocentrals numerous, hair-like, short, scarcely longer than acrostichals. Tarsi of all legs with black tarsomere 5 (or 4–5);

apical spur on mid tibia short, scarcely as long as width of tibia; darker and with tiny curved hair at tip in male, flattened and blunt-tipped in female............................................................. P. cothurnatus Macquart 21 (19) Postpedicel longer, at least 2.5X as long as wide; stylus equal to, or at least not very much longer than postpedicel...... 22

- Postpedicel shorter, at most twice as long as wide; stylus at least 1.5X longer than postpedicel...................... 24

22 (21) Clypeus polished black. Postpedicel about 2.5X longer than wide. Tarsomeres of all legs broadly sharply black annulated. Abdomen black, entirely shiny......................................... P. arzanovi Kustov, Shamshev & Grootaert

- Clypeus grey dusted. Different combination of characters................................................... 23

23 (22) Vertical bristles separated nearly 1.5X width of frons opposite anterior ocellus. Legs with mid femur very conspicuously thickened, much stouter than fore femur; yellow with mid knees conspicuously brownish black, tarsi with faint dark annulations. Usually 3 notopleural bristles present. Abdomen with small grey lateral patches on anterior two tergites, otherwise shiny. Male: left epandrial lamella with dorsal outgrowth. Female: sternite 8 with swollen polished lateral parts...................................................................................................... P. infectus (Collin)

- Vertical bristles more widely separated than above. Mid femur more slender, not much stouter than fore femur. Legs extensively darkened, at least fore coxa at base, whole of posterior four coxae and posterior four femora near tip dark brown. Only 2 notopleural bristles present. Abdomen entirely shiny. Male: left epandrial lamella without dorsal outgrowth. Female: sternite 8 without swollen polished lateral parts....................................................... P. n o ta t u s (Meigen)

24 (21) Abdomen almost entirely polished black, only tergites 1–2 faintly pollinose laterally. Postpedicel only slightly longer than deep, stylus nearly 4X as long.......................................................... P. clarandus (Collin)

- Abdomen with greyish lateral patches on all tergites. Postpedicel nearly twice as long as wide; stylus 1.5– 2 X longer than postpedicel........................................................................................... 25

25 (24) Abdomen with sternites entirely grey dusted. Palpus yellowish................................... P. collini (Chvála)

- Abdomen with sternites entirely shiny. Palpus brown....................................... P. teberdaensis sp. nov.

26 (18) Thoracic pleura densely grey dusted, including katepisternum................................................ 27

- Katepisternum with polished patch....................................................................... 30

27 (26) Two notopleural bristles. Postpedicel entirely brownish black. Abdomen bicoloured, with black tergites and yellowish sternites................................................................ P. o d i n ts o v i Kustov, Shamshev & Grootaert

- Three notopleural bristles. Postpedicel yellowish at least on extreme base. Abdomen uniformly black in ground-colour.. 28

28 (27) Abdomen with sternites dusted........................................................ P. caucasicus Kovalev

- Abdomen with sternites shiny......................................................................... 29

29 (28) Postpedicel nearly 1.5X longer than wide; stylus nearly 3X longer than postpedicel............. P. kintrishiensis sp. nov.

- Postpedicel nearly 3X longer than wide; stylus nearly 1.5X longer than postpedicel............. P. subcaucasicus sp. nov.

30 (26) Posthumeral bristle present. Fore and hind tibiae with distinct dark, stronger setae dorsally......................... 31

- Posthumeral bristle absent. Fore and hind tibiae covered with only short, hair-like setae........................... 34

31 (30) Postpedicel entirely black. Fore tarsomeres with distinct dark annulations. Crossveins m-cu and r-m broadly separated. Abdomen extensively polished black....................................................... P. pallidiventris (Meigen)

- Postpedicel yellowish at base. Fore tarsi with only tarsomere 5 brownish. Different combination of characters than above... 32

32 (31) Abdominal tergites broadly pollinose anteriorly and laterally. Crossveins m-cu and r-m contiguous..................................................................................... P. abagoensis Kustov, Shamshev & Grootaert

- Abdomen almost entirely polished black, only tergites 1–2 with small lateral grey spots. Crossveins m-cu and r-m separated................................................................................................... 33

33 (32) Postpedicel narrowly yellowish at extreme base. Fore tarsomere 5 blackish, mid and hind tarsomeres blackish annulated..................................................................................... P. longiseta (Zetterstedt)

- Postpedicel pale yellow on basal half. Only tarsomere 5 of all legs brown on apical half, otherwise tarsi yellow.............................................................................................. P. akhunensis sp. nov. (Differences between females of these species are unclear.)

34 (30) Antenna entirely yellow, at most postpedicel slightly darkened at extreme tip.................................... 35

- Postpedicel black at least on apical half.................................................................. 36

35 (34) Acrostichals irregularly 3–4-serial. Tarsi of all legs yellow with only last segment blackish apically. Palpus pointed apically. Mid tibial spur blunt in male, more pointed in female..................................... P. albicornis (Zetterstedt)

- Acrostichals biserial. Tarsomeres 2–5 of all legs indistinctly annulated (darker on tarsomeres 3–5). Palpus rounded apically. Mid tibial spur long and pointed in both sexes..................... P. kamyshanovensis Kustov, Shamshev & Grootaert

36 (34) Postpedicel yellow on about basal third. Fore femur brownish on about basal half. Abdomen entirely black and shiny.................................................................... P. neberdzaensis Kustov, Shamshev & Grootaert

- Postpedicel entirely black. Fore femur yellow. Abdomen with sternites 1–2 brownish yellow to yellowish; tergites 1–2 pollinose at sides anteriorly (see also section 25)........................................... P. clarandus (Collin)

37 (9) Hind tibia with several long black bristles dorsally at least as long as width of tibia........ P. pseudosilvahumidus sp. nov.

- Hind tibia without prominent bristles.................................................................... 38

38 (37) Mesonotum polished black, at least on posterior third. Apical spur on mid tibia absent or very small, not longer than width of tibia............................................................................................... 39

- Mesonotum entirely greyish or yellowish-grey dusted, even if only thinly so. Apical spur on mid tibia absent or present ... 40

39 (38) Mid femur without posteroventral bristles; legs, including coxae, yellow, only tarsi darkened. Frons and vertex greyish dusted. Meron dusted; acrostichals and dorsocentrals rather long, pale and numerous................... P. longicornis (Meigen)

- Mid femur with back posteroventral bristles; legs rather darker yellow to brownish yellow, with mid and hind coxae, most of fore tibia, patch on mid femur, apical third of hind femur, and tarsi blackish. Frons and vertex shiny. Meron shiny; acrostichals

and dorsocentrals fine and inconspicuous................................................. P. nigritarsis (Fallén) 40 (38) Apical spur on mid tibia absent or very small, at most as long as width of tibia. Basal antennal segments often yellowish. 41

- Mid tibia with long, sharply pointed apical spur, much longer than width of tibia. Antenna always black.............. 46

41 (40) Acrostichals 2-serial. Mid femur rather slender, at most only slightly broader than fore femur........................ 42

- Acrostichals at least 3–4-serial. Mid femur distinctly broader than fore femora................................... 44

42 (41) Postpedicel short, at most twice as long as deep. Legs mostly yellow, mid coxa, hind coxa and trochanter brownish, fore and mid tarsi brownish yellow, hind tarsus brownish......................... P. gazaryani Kustov, Shamshev & Grootaert

- Postpedicel longer and narrower, at least 3X as long as deep. Legs with different pattern........................... 43

43 (42) Antenna with postpedicel very long at least 5X as long as wide; stylus very short, about 1/4 length of postpedicel. Legs rather dirty yellowish, tarsi extensively darker brown, and tibiae more or less brown................... P. brachystylus (Bezzi)

- Antenna with postpedicel almost 4X as long as deep; stylus half as long as postpedicel. Legs yellow to dirty yellow, last tarsal segment contrastingly black, preceding two segments often light brownish..................... P. luteicornis (Meigen)

44 (41) Mid femur with row of posteroventral bristles. Antenna with scape and pedicel yellow to brownish; postpedicel black, slightly longer than wide. Palpus pale. Mid tibia with very small, blunt apical spur................... P. brevicornis (Zetterstedt)

- Mid femur without posteroventral bristles. Different combination of characters.................................. 45

45 (44) Antenna entirely black; postpedicel long, pointed, at least 3X as long as wide. Face with dense silvery pollinosity; clypeus shiny. Male: hind trochanter without spines. Larger, body more than 3 mm ........................... P. sinevi sp. nov.

- Antenna with scape and pedicel yellowish; postpedicel black, short and broad, 1.5X as long as wide. Face somewhat velvety dark pinkish grey, very different from paler silvery pilose clypeus, Male: hind trochanter with 3 long black spines. Smaller, body 1.4–1.6 mm ....................................................................... P. vegrandis Frey

46 (40) Acrostichals irregularly 6-serial on broad median stripe, at least anteriorly. Large thoracic bristles black. Antenna with postpedicel very short and broad, almost spherical. Legs extensively black; all coxae and femora black except for tip of fore femur; hind tibia darkened at tip; tarsi with last tarsomere blackish. Mid tibia with long, sharply pointed apical spur, distinctly longer than width of tibia. Mid femur with distinct black posteroventral bristles.......................... P. rapidoides Chvála

- Acrostichals 2-serial throughout. Different combination of characters.......................................... 47

47 (46) Postpedicel about 3X as long as wide. Stylus about as long or slightly longer than postpedicel........ P. baldensis (Strobl)

- Postpedicel about 2X as long as deep. Stylus at least 2X longer than postpedicel................................. 48

48 (47) Stylus 3.5X longer than postpedicel. Abdominal tergites densely greyish dusted leaving shiny dorsal subtriangular spots posteriorly................................................................................ P. lantsovi sp. nov.

- Stylus 2X longer than postpedicel. Abdomen largely polished black, basal two segments with small greyish patches at sides...................................................................................... P. nigrinus (Meigen)