Cryptotendipes Beck et Beck, 1969

Mukherjee, Bindarika, Mukherjee, Tuhar & Hazra, Niladri, 2020, A new species of the genus Cryptotendipes Beck et Beck, 1969 (Diptera Chironomidae) from India, with a world key to the males and tentative phylogenetic relationship, Zootaxa 4896 (2), pp. 201-223 : 210-218

A world key to the species of the genus Cryptotendipes Beck et Beck (male)

(modified after Pal et Hazra, 2018)

1. Inner margin of gonostylus with basal or median projection.................................................. 2

- Inner margin of gonostylus without projection............................................................ 24

2(1). Inner margin of gonostylus with median projection......................................................... 3

- Inner margin of gonostylus with basal projection.......................................................... 13

3(2). Anal point not longer than superior volsella............................................................... 4

- Anal point longer than superior volsella.................................................................. 6

4(3). Gonostylus with distinct concavity in apical half.............................. C. tuberosus Saether, 2010 (Nearctic)

- Gonostylus without distinct concavity................................................................... 5

5(4). Superior volsella columniform and straight; anal point rounded at apex...... C. nigronitens ( Edwards, 1929) (Palaearctic)

- Superior volsella digitiform and curved; anal point pointed at apex............. C. pflugfelderi Reiss, 1964 (Palaearctic)

6(3). Anal tergite with high ridge or keel lies dorsally............................................................ 7

- Anal tergite without ridge or keel....................................................................... 8

7(6). Acrostichals 1–7; dorsal ridge on proximal part of TIX....................... C. casuarius ( Townes, 1945) (Holarctic)

- Acrostichals absent; dorsal protrusion on distal part of TIX.................... C. lyalichi ( Zorina, 2006) (Palaearctic)

8(6). Anal point with setae in basal half...................................................................... 9

- Anal point without setae............................................................................. 10

9(8). AR greater than 2.00; superior volsella with 2–3 apical setae and without lateral setae................................................................................................. C. usmaensis ( Pagast, 1931) (Palaearctic)

- AR less than 2.00; superior volsella with 1 apical seta and 2 lateral setae.... C. tobatertius Kikuchi et Sasa, 1990 (Oriental)

10(8). Superior volsella with microtrichia only at base; inner margin of gonostylus sharply incised after proximal half.............................................................................. C. emorsus ( Townes, 1945) (Holarctic)

- Superior volsella with or without microtrichia; gonostylus smoothly curved, without any sharp concavity............. 11

11(10). Superior volsella distinctly bilobed............................. C. daktylos (Walley in Curran, 1934) (Neotropical)

- Superior volsella not bilobed......................................................................... 12

12(11). Superior volsella curved, swollen at apex and truncated; anal point tapering to point...................................................................................................... C. pilicuspis Saether, 1977 (Nearctic)

- Superior volsella straight, not swollen at apex; anal point parallel–sided to point........................................................................................... C. parallelus Yan, Tang et Wang, 2005 (Palaearctic)

13(2). Small digitiform lobe lies nearer to middle of anal point.................................................... 14

- Anal point without lobe.............................................................................. 19

14(13). Long setae of inner margin of gonostylus lies proximally ( Figs. 1 D–E)..................... C. medialis sp.n. (Oriental)

- Long setae of gonostylus present on entire inner margin.................................................... 15

15(14). Tergite IX without dorsal or ventral lobes................................................................ 16

- Tergite IX with pair of dorsal or ventral lobes............................................................ 17

16(15). Gonostylus with basal 1/3 moderately inflated; superior volsella apically triangular ( Figs. 3 A–B)........................................................................................ C. disparilis Pal et Hazra, 2018 (Oriental)

- Gonostylus with basal 2/3 moderately inflated; superior volsella digitoform............ C. rutteri Epler, 2018 (Nearctic)

17(15). Frontal tubercles absent; superior volsella pointed at apex, without microtrichia.............................................................................................. C. tobasecundus Kikuchi et Sasa, 1990 (Oriental)

- Frontal tubercles present; superior volsella obtuse at apex, covered by microtrichia.............................. 18

18(17). Bands of T IX fused; superior volsella constricted in middle, widened at apex........ C. acalcar Reiss, 1990 (Palaearctic)

- Bands of T IX separated; superior volsella slightly swollen in middle, rounded at apex...................................................................................... C. mongolkeleus ( Sasa et Suzuki, 1997) (Palaearctic)

19(13). Tergite IX with distinct caudolateral shoulders.............................. C. darbyi ( Sublette, 1960) (Holarctic)

- Tergite IX without caudolateral shoulders............................................................... 20

20(19). Superior volsella covered by microtrichia............................................................... 21

- Superior volsella without microtrichia.................................................................. 22

21(20). AR 2.26–2.66; gonostylus obtuse at apex....................... C. mongoljekeus ( Sasa et Suzuki, 1997) (Palaearctic)

- AR 3.1–3.5; gonostylus pointed at apex....................................... C. ariel ( Sublette, 1960) (Nearctic)

22(20). Anal point without lateral setae..................................... C. nodus Yan, Tang et Wang, 2005 (Oriental)

- Anal point with lateral setae.......................................................................... 23

23(22). Apex of anal point truncated; superior volsella either with 2 apical setae or 2 apical and 1 subapical setae............................................................................. C. daitogeheus Sasa et Suzuki, 2001 (Oriental)

- Apex of anal point swollen; superior volsella with 2 apical setae ( Figs. 2 A–B).. C. aculeatus Pal et Hazra, 2018 (Oriental)

24(1). Gonostylus apically pointed; superior volsella with 1 apical and 3 subapical setae.... C. holsatus Lenz, 1959 (Palaearctic)

- Gonostylus apically rounded; superior volsella with 2 subapical and 2 apical setae.............................................................................................. C. pseudotener ( Goetghebuer, 1922) (Holarctic)

Figures

FIGURES 1A–E. Adult male Cryptotendipes medialis sp. n. A. Wing, B. Anal point, C. Superior volsella, D. Hypopygium (photograph), E. Hypopygium, scale. 0.01 mm.

FIGURES 2A–B. Adult male Cryptotendipes aculeatus Pal et Hazra, 2018. A. Hypopygium (photograph), B. Hypopygium, scale. 0.01mm.

FIGURES 3A–B. Adult male Cryptotendipes disparilis Pal et Hazra, 2018. A. Hypopygium (photograph), B. Hypopygium, scale. 0.01mm.

4(3). Gonostylus with distinct concavity in apical half.............................. C. tuberosus Saether, 2010 (Nearctic)

5(4). Superior volsella columniform and straight; anal point rounded at apex...... C. nigronitens ( Edwards, 1929 ) (Palaearctic)

- Superior volsella digitiform and curved; anal point pointed at apex............. C. pflugfelderi Reiss, 1964 (Palaearctic)

7(6). Acrostichals 1–7; dorsal ridge on proximal part of TIX....................... C. casuarius ( Townes, 1945 ) (Holarctic)

- Acrostichals absent; dorsal protrusion on distal part of TIX.................... C. lyalichi ( Zorina, 2006 ) (Palaearctic)

9(8). AR greater than 2.00; superior volsella with 2–3 apical setae and without lateral setae................................................................................................. C. usmaensis ( Pagast, 1931 ) (Palaearctic)

- AR less than 2.00; superior volsella with 1 apical seta and 2 lateral setae.... C. tobatertius Kikuchi et Sasa, 1990 (Oriental)

10(8). Superior volsella with microtrichia only at base; inner margin of gonostylus sharply incised after proximal half.............................................................................. C. emorsus ( Townes, 1945 ) (Holarctic)

11(10). Superior volsella distinctly bilobed............................. C. daktylos (Walley in Curran, 1934 ) (Neotropical)

12(11). Superior volsella curved, swollen at apex and truncated; anal point tapering to point...................................................................................................... C. pilicuspis Saether, 1977 (Nearctic)

- Superior volsella straight, not swollen at apex; anal point parallel–sided to point........................................................................................... C. parallelus Yan, Tang et Wang, 2005 (Palaearctic)

- Gonostylus with basal 2/3 moderately inflated; superior volsella digitoform............ C. rutteri Epler, 2018 (Nearctic)

17(15). Frontal tubercles absent; superior volsella pointed at apex, without microtrichia.............................................................................................. C. tobasecundus Kikuchi et Sasa, 1990 (Oriental)

18(17). Bands of T IX fused; superior volsella constricted in middle, widened at apex........ C. acalcar Reiss, 1990 (Palaearctic)

- Bands of T IX separated; superior volsella slightly swollen in middle, rounded at apex...................................................................................... C. mongolkeleus ( Sasa et Suzuki, 1997 ) (Palaearctic)

19(13). Tergite IX with distinct caudolateral shoulders.............................. C. darbyi ( Sublette, 1960 ) (Holarctic)

21(20). AR 2.26–2.66; gonostylus obtuse at apex....................... C. mongoljekeus ( Sasa et Suzuki, 1997 ) (Palaearctic)

- AR 3.1–3.5; gonostylus pointed at apex....................................... C. ariel ( Sublette, 1960 ) (Nearctic)

24(1). Gonostylus apically pointed; superior volsella with 1 apical and 3 subapical setae.... C. holsatus Lenz, 1959 (Palaearctic)

- Gonostylus apically rounded; superior volsella with 2 subapical and 2 apical setae.............................................................................................. C. pseudotener ( Goetghebuer, 1922 ) (Holarctic)