Trichocoelina absidata Vilkamaa & Menzel 2019, sp. n.

T. absidata sp. n. (Russia: Krasnodarsk region)

T. aemula sp. n. (Finland; Russia: Krasnodarsk region)

T. biplex sp. n. (Canada: Newfoundland and Labrador, Yukon)

T. brevicubitalis (Lengersdorf, 1926) comb. n. (Norway: mainland;? Estonia)

T. chentejensis (Menzel, 1992) comb. n. (Finland; Mongolia)

T. cochleata (Rübsaamen, 1898) comb. n. (Czech Republic; Finland; Russia: Karelia, Siberia; Norway: mainland, Svalbard; Greenland)

T. dicksoni sp. n. (Russia: Arkhangelsk oblast, Kemerovsk oblast, Krasnodarsk region)

T. dispansa sp. n. ( Russia: Krasnodarsk region)

T. dividua sp. n. (Canada: Northwest Territories)

T. hians sp. n. (Canada: Yukon)

T. hiemalis (Mohrig & Mamaev, 1985) comb. n. (Finland; Germany; Russia: Krasnodarsk region)

T. imitator sp. n. (Canada: Yukon)

T. incrassata sp. n. (USA: Alaska)

T. ithyspina sp. n. (Norway: mainland)

T. janetscheki (Lengersdorf, 1953) comb. n. (Austria; Greenland; Canada: Nunavut; USA: Colorado)

T. jukkai sp. n. (Finland; Norway: mainland)

T. magnifica sp. n. (Canada: Yukon)

T. nefrens sp. n. (Russia: Krasnodarsk region)

T. obesula sp. n. (Norway: Svalbard)

T. olschwangi (Mohrig & Mamaev, 1983) comb. n. (Russia: Krasnodarsk region; Canada: Yukon; USA: Colorado)

T. oricillifera sp. n. (Finland; Norway: mainland; Sweden)

T. planilobata sp. n. (Finland)

T. quintula sp. n. (Finland)

T. semisphaera sp. n. (Finland; Norway: Svalbard)

T. semusta sp. n. (Italy; USA: Alaska)

T. subcochleata (Komarov, 2009) comb. n. (Russia: Republic of Altai)

T. subpermutata (Mohrig & Mamaev, 1990) comb. n. (Russia: Krasnodarsk region; Sweden)

T. tecta sp. n. (Russia: Krasnodarsk region, Yamalo-Nenets Autonomous Okrug; Canada: Nunavut, Yukon; USA: Alaska)

T. vitticollis (Holmgren, 1883) comb. n. (Finland; Norway: Svalbard; Russia: Novaya Zemlya; Sweden; Greenland;? Canada: Nunavut)

Key to species of Trichocoelina (males)

Note. Trichocoelina brevicubitalis (Lengersdorf, 1926) comb. n., known only in the female sex, is not included in the identification key (redescription and discussion see under ‘The Trichocoelina species’).

1 Apical tooth of gonostylus present....................................................................... 2

- Apical tooth of gonostylus absent............................................................ T. nefrens sp. n.

2 Megaseta present on apical (lateral) side of apical tooth of gonostylus........................................... 3

- Megaseta absent from apical (lateral) side of apical tooth of gonostylus.......................................... 6

3 Intergonocoxal lobe extremely broad, medially slightly notched................................. T. planilobata sp. n.

- Intergonocoxal lobe(s) narrower......................................................................... 4

4 Tegmen and intergonocoxal lobe much broader than long........................................ T. dispansa sp. n.

- Tegmen and intergonocoxal lobe at most slightly broader than long............................................. 5

5 Tegmen apically and laterally roundish, gonostylus sparsely setose, gonostylar megasetae slender, intergonocoxal lobe at most apically bifid............................................................................. T. jukkai sp. n.

- Tegmen apically and laterally straight, gonostylus richly setose, gonostylar megasetae thicker, intergonocoxal lobe deeply divided................................................................................. T. dividua sp. n.

6 Megaseta(e) present on the ventral side of apical tooth or adjacent on its basal side................................. 7

- Megaseta(e) absent from the ventral side of apical tooth, none adjacent on its basal side............................. 9

7 Gonostylus broad, all gonostylar megasetae much narrower than apical tooth at its base................. T. obesula sp. n.

- Gonostylus narrow, the basalmost megasetae only slightly narrower than apical tooth at its base...................... 8

8 Hypopygium with one elongated, apically bifid intergonocoxal lobe................................ T. ithyspina sp. n.

- Hypopygium with two separate triangular intergonocoxal lobes.............................. T. chentejensis (Menzel)

9 Tegmen with distinct lateral teeth or corners, or strongly narrowed at middle..................................... 10

- Tegmen without lateral teeth or corners, laterally straight or smoothly curved.................................... 16

10 One of gonostylar megasetae with its basal body separated from others and larger.................... T. magnifica sp. n.

- None of gonostylar megasetae with their basal bodies separated, or larger than the others........................... 11

11 All gonostylar megasetae pointing at one direction, either perpendicularly or obliquely............................. 12

- Some groups of gonostylar megasetae pointing perpendicularly, some obliquely.................................. 14

12 Gonostylus rather narrow with narrowed apex, with long apical tooth and oblique megasetae.............. T. biplex sp. n.

- Gonostylus voluminous, with tumid apex, with short apical tooth and megasetae.................................. 13

13 Tegmen apicad from the lateral corners short, basally strongly broadened, intergonocoxal lobes long.... T. oricillifera sp. n.

- Tegmen apicad from the lateral corners long, basally slightly broadened, intergonocoxal lobes short....... T. imitator sp. n.

14 Gonostylus very broad, laterally semicircular, with dorsomedial lobe, tegmen with straight apicolateral sides.................................................................................................. T. incrassata sp. n.

- Gonostylus narrower, laterally less curved, without dorsomedial lobe, tegmen with sharp lateral corners............... 15

15 Intergonocoxal area of hypopygium with 1 long, apically divided lobe, tegmen longer than broad.................................................................................................... T. subcochleata (Komarov)

- Intergonocoxal area with 2 short separate lobes, tegmen broader than long........... T. subpermutata (Mohrig & Mamaev)

16 Gonostylus with one group of megasetae, with megasetae pointing in different directions..................................................................................................... T. olschwangi (Mohrig & Mamaev)

- Gonostylus with groups of megasetae, in each group megasetae pointing in only one direction....................... 17

17 Gonostylus with both perpendicular and oblique groups of megasetae................................. T. tecta sp. n.

- Gonostylus with only perpendicular or oblique groups of megasetae........................................... 18

18 Gonostylar megasetae perpendicular............................................................ T. hians sp. n.

- Gonostylar megasetae oblique.......................................................................... 19

19 Intergonocoxal area with 1 lobe, divided at apical half....................................................... 20

- Intergonocoxal area with 2 separate lobes................................................................. 21

20 Gonostylus subtriangular, basally broad, apically strongly narrowed............................. T. semisphaera sp. n.

- Gonostylus basally not especially broad and apically only slightly narrowed.................... T. vitticollis (Holmgren)

21 Gonostylus very large, with about 30 short megasetae, tegmen with acuminate hyalinous apical process............................................................................................... T. janetscheki (Lengersdorf)

- Gonostylus smaller, with at most 15 megasetae, tegmen without apical process or with a curved one.................. 22

22 Tegmen with semicircular sclerotized apical process, apex of gonostylus with strikingly dark setosity................. 23

- Tegmen without apical process, apex of gonostylus not strikingly dark.......................................... 24

23 Apical process of tegmen narrow and protruding, antennal scapus and pedicellus yellow........ T. cochleata (Rübsaamen)

- Apical process of tegmen broad, not protruding, antennal scapus and pedicellus brown.................. T. semusta sp. n.

24 Gonostylus narrow, about 2.4x as long as wide, with 5 megasetae.................................. T. quintula sp. n.

- Gonostylus broad, 1.7–2x as long as broad, with at least 7 megasetae........................................... 25

25 Apical tooth of gonostylus distinctly longer than gonostylar megasetae............................. T. absidata sp. n.

- Apical tooth of gonostylus subequal with gonostylar megasetae............................................... 26

26 Apical tooth of gonostylus and gonostylar megasetae relatively long, about 2/5 of the broadest part of gonostylus................................................................................................ T. aemula sp. n.

- Apical tooth of gonostylus and gonostylar megasetae relatively short, about 1/4–1/3 of the broadest part of gonostylus... 27

27 Gonostylus distinctly narrowed towards apex, its lateral side strongly curved, tegmen semicircular............................................................................................... T. hiemalis (Mohrig & Mamaev)

- Gonostylus apically truncate, its lateral side slightly curved, tegmen subtriangular.................... T. dicksoni sp. n.

The Trichocoelina species