Cryptotendipes acutus ( Goetghebuer, 1936 ) Mukherjee & Hazra, 2023

Mukherjee, Bindarika & Hazra, Niladri, 2023, Taxonomic studies on Harnischia complex from India (Diptera: Chironomidae), Zootaxa 5278 (2), pp. 239-263 : 248-251

Cryptotendipes acutus ( Goetghebuer, 1936) , Comb.n.

GenBank accession number. MW012424

Harnischia acuta ( Goetghebuer, 1936) : Sasa & Hasegawa, 1983: 323; Hazra, Niitsuma & Chaudhuri, 2016: 77 Parachironomus acutus ( Goetghebuer, 1936) : Yan et al., 2015: 34

Cryptotendipes disparilis Pal & Hazra, 2018: 37 ; Mukherjee et al., 2020: 206, Syn. n.

Material examined. Holotype male labelled ‘ Holotype Cryptotendipes disparilis Pal & Hazra, 2018 , India, West Bengal, Malda [24.90°N, 88.11°E], 06.ii.2013, Coll. G. Pal’. 2 males, India, West Bengal, Purba Barddhaman, Burdwan [23.22°N, 87.85°E], 23.xii.2019, Coll. N. Hazra; 2 males, India, West Bengal, Purba Barddhaman, Burd_ wan [23.22°N, 87.85°E], 15.i.2020, Coll. N. Hazra; 5 males, India, West Bengal, Purba Barddhaman, Burdwan [23.22°N, 87.85°E], 16.ii.2020, Coll. N. Hazra; 2 males, India, West Bengal, Birbhum [24.435°N, 87.911°E], 10.iv.2022, Coll. B. Mukherjee.

Diagnosis. The species have V shaped anal tergite band; superior volsella distally somewhat triangular in shape bearing two apical setae and gonostylus basally expanded, gradually tapered distally with a nipple-like apex bearing single seta.

Remarks. Sasa & Hasegawa (1983) tentatively placed the species into the genus Harnischia , described by Goetghebuer, 1936 as Chironomus (Harnischia) acutus . Yan et al. (2015) tentatively transferred this species into Parachironomus . Pal and Hazra (2018) described Cryptotendipes disparilis from India. After an extensive study of specimens, we have been able to affirm its placement in the genus Cryptotendipes Beck & Beck along with synonymisation of other known species with Cryptotendipes acutus . The combination of those characters in male imagines justifying the placement and synonymy includes gonostylus with strong basal expansion and superior volsella having two apical setae not arising from conspicuous pits. Other significant characters are: total length 2.98–3.27, 3.13 mm; eyes with dorsomedian parallel sided extension of 150–180, 165 µm; AR 1.9–2.07, 1.99; CA 0.61–0.66, 0.63; Ac 12–14, Dc 7–8, Pa 3–5, Scts 8–10; vein R with 42–46, R 1 30–32, R 4+5 12–14 setae; VR 1.26– 1.33, 1.3; T IX with 19–22, 20 median long setae; anal point 72.3–80, 75 µm long with 2–3 basolateral setae on each side; gonocoxite 165–172, 168 µm long; superior volsella 23–27.6, 25 µm long, 11.5–14, 12 µm wide; transverse sternapodeme 55–59, 57 µm long, lateral sternapodeme 128–134, 131 µm long; HR 1.2–1.27, 1.23.

Distribution. Egypt, Israel, Chad, Congo, Ethiopia, Kenya, Nigeria, South Africa, Japan, India.

World Key to the species of the genus Parachironomus Lenz (male)

1. Gonostylus with strongly basal expansion (Nearctic)..................................... P. subletti ( Beck, 1961)

- Gonostylus not with above combination................................................................. 2

2(1). Superior volsella short and thick........................................................................ 3

- Superior volsella slender.............................................................................. 4

3(2). Tibial spurs absent (Neotropics)...................................................... P. robustus Paggi, 1979

- Tibial spur present (Neotropics).......................................... P. mirim Spies, Fittkau & Reiss, 1994

4(2). Superior volsella short................................................................................ 5

- Superior volsella elongated........................................................................... 10

5(4). Anal point with broad rounded apex (Afrotropics).............................. P. nigrofasciatus ( Freeman, 1961b)

- Anal point slender................................................................................... 6

6(5). Anal point very long; gonostylus slightly swollen at basal area (Afrotropics)........ P. dewulfianus (Goetghebuer, 1934)

- Anal point variably developed; gonostylus parallel shaped or tapered.......................................... 7

7(6). Anal point short, curved ventrally (Nearctic)..................................... P. schneideri Beck & Beck, 1969

- Anal point moderately long, variably developed........................................................... 8

8(7). Gonostylus medially constricted; superior volsella cylindrical with 2 setae located side by side (Orient, Palaearctic)................................................................................... P. gracilior ( Kieffer, 1918a)

- Gonostylus evenly tapered; superior volsella finger-like with two setae located opposite to each other................ 9

9(8). Anal point with pointed apex; superior volsella nearly straight (Palaearctic)..................... P. kujini Shilova, 1969

- Anal point distally widened; superior volsella curved distally (Palaearctic)............... P. biannulatus ( Staeger, 1839)

10(4). Superior volsella with apical or apico-lateral projections.................................................... 11

- Superior volsella without apico-lateral projection......................................................... 28

11(10). Superior volsella distally swollen with an inner apical lobe (Afrotropics, Palaearctic)....... P. aculeatus ( Kieffer, 1921b)

- Superior volsella with rounded or cone-like projection at apical end.......................................... 12

12(11). Gonostylus straight or with little bent................................................................... 13

- Gonostylus strongly curved medially or distally........................................................... 17

13(12). Superior volsella with low projection arising from lateral rim of terminal setal pit (Nearctic).................................................................................................. P. hirtalatus Beck & Beck, 1964

- Superior volsella with strong projection arising from several parts around the setal pit............................ 14

14(13). Anal tergite band separate............................................................................ 15

- Anal tergite band fused.............................................................................. 16

15(14). Laterosternite IX with 0–1 seta; bare part of anal point relatively short (Palaearctic)............. P. aequilonis Orel, 2017

- Laterosternite IX with 3–4 setae; bare part of anal point relatively long (Holarctic)............. P. hazelriggi Spies, 2000

16(14). Median longitudinal band absent; anal tergite with well-developed triangular ventrolateral shoulder on posterior margin (Holarctic).............................................................. P. subalpinus ( Goetghebuer, 1931)

- Median longitudinal band present; ventrolateral shoulder on posterior margin of anal tergite weakly developed (Palaearctic)................................................................................. P. khatyrka Orel, 2017

17(12). Superior volsella with low rounded apical projection....................................................... 18

- Superior volsella with prominent variable-shaped apical projection........................................... 20

18(17). Superior volsella strongly sinuous at apex and median setal pit wide covering entire apical surface (Holarctic)........................................................................................ P. digitalis ( Edwards, 1929)

- Superior volsella slightly wide at apex, both setal pits with same width........................................ 19

19(18). Superior volsella with small triangular cusp like projection subapically; anal point slender and tapered; gonostylus swollen medially (Nearctic).............................................................. P. forceps ( Townes, 1945)

- Superior volsella with small beak-like projection apicol-leterally; anal point rounded at apex; gonostylus mostly swollen subapically (Nearctic)............................................................ P. potamogeti ( Townes, 1945)

20(17). Anal point nearly widened at apex..................................................................... 21

- Anal point slender and tapered at apex.................................................................. 23

21(20). Anal tergite band fused and Y type; apical projection of superior volsella serrated (Neotropics)............................................................................................. P. tirio Spies, Fittkau & Reiss, 1994

- Anal tergite band separated; apical projection of superior volsella smooth...................................... 22

22(21). Gonostylus basally swollen; base of anal tergite with 14–16 setae (Palaearctic)............. P. pseudovarus Zorina, 2003

- Gonostylus medially swollen; base of anal point without setae (Nearctic).................. P. gillespiaeae Spies, 2000

23(20). Superior volsella reaching midth of gonostylus (Holarctic)......................... P. tenuicaudatus (Malloch, 1915)

- Superior volsella extend beyond base of gonostylus........................................................ 24

24(23). Gonostylus with narrow base and inner margin distinctly curved............................................. 25

- Gonostylus without narrow base and inner margin straight.................................................. 27

25(24). In distal half, outer margins of gonostylus swell notably (Holarctic)...................... P. varus ( Goetghebuer, 1921)

- In distal half, outer margin of gonostylus swell very little.................................................. 26

26(25). Median anal tergite setae above base of anal point slender and few in number; on distal part of gonostylus microtrichia absent (Palaearctic)........................................................... P. swammerdami ( Kruseman, 1933)

- Median anal tergite setae above base of anal point stronger and numerous; on distal part of gonostylus microtrichia present (Palaearctic)................................................................ P. mauricii ( Kruseman, 1933)

27(24). Thorax with mesonotal stripes; gonostylus equally broad at its basal and distal end (Palaearctic)............................................................................................... P. paradigitalis ( Brundin, 1949)

- Thorax without mesonotal stripes; gonostylus swollen at base than distal part (Holarctic)........ P. parilis ( Walker, 1856)

28(10). Superior volsella with 3 setae (Palaearctic)......................................... P. siljaensis ( Brundin, 1949)

- Superior volsella with 2 setae......................................................................... 29

29(28). Gonostylus sharply pointed at apex..................................................................... 30

- Gonostylus bluntly pointed at apex..................................................................... 51

30(29). Anal point stout throughout; superior volsella curving outwardly (Nearctic).................... P. alatus ( Beck, 1962)

- Anal point and superior volsella not with above combination................................................ 31

31(30). Setal bases of two setae of superior volsella not prominent (Palaearctic).............. P. cinctellus ( Goetghebuer, 1921)

- Setal bases prominent............................................................................... 32

32(31). Gonostylus swollen medially at inner side and then tapered.................................................. 33

- Gonostylus variable shaped........................................................................... 34

33(32). Superior volsella shorter than anal point; gonostylus parallel-sided (Afrotropics)............. P. coronatus ( Kieffer, 1922)

- Superior volsella and anal point nearly equal in length; gonostylus strongly recurved apically (Nearctic)................................................................................. P. pectinatellae ( Dendy & Sublette, 1959)

34(32). Gonostylus spatulated or almost straight................................................................. 35

- Gonostylus basally or pre-apically widened.............................................................. 47

35(34). Superior volsella with a beak-like projection at apex bearing two setae originating from two distinct bases of same width (Holarctic)................................................................ P. vitiosus ( Goetghebuer, 1921)

- Superior volsella variable shaped, two setal bases have either similar width or not................................ 36

36(35). Superior volsella rod-like, widest apically............................................................... 37

- Superior volsella variable shaped...................................................................... 46

37(36). Superior volsella cylindrical entirely.................................................................... 38

- Superior volsella apically or preapically sinuated......................................................... 39

38(37). Anal point slender, have rounded apex; anal tergite band fused medially (Nearctic).......... P. carinatus ( Townes, 1945)

- Anal point very broad; anal tergite band fused inside base of anal point (Neotropics).................................................................................................... P. apalai Spies, Fittkau & Reiss, 1994

39(37). Superior volsella with a keel-like structure at sub-apical end (Nearctic)............. P. directus ( Dendy & Sublette, 1959)

- Superior volsella without keel-like structure.............................................................. 40

40(39). Anal tergite band fused.............................................................................. 41

- Anal tergite band separated........................................................................... 44

41(40). Anal tergite with lateral projection..................................................................... 42

- Anal tergite without lateral projection................................................................... 43

42(41). Each lateral projection bearing low dorsal sub-lobe; tergite IX with 1 medio-dorsal seta (Neotropics).................................................................................... P. camajura Spies, Fittkau & Reiss, 1994

- Low lateral projection without dorsal sub-lobe; tergite IX with 15 setae (Neotropics).................................................................................................... P. waika Spies, Fittkau & Reiss, 1994

43(41). Longitudinal band forming a mesh around base of anal tergite; median connection of Y shaped anal tergite band weak (Nearctic, Neotropics)................................................. P. guarani Spies, Fittkau & Reiss, 1994

- Longitudinal band thin and straight; median connection of tergite band strong (Neotropics)............................................................................................. P. aberrans Spies, Fittkau & Reiss, 1994

44(40). Anal tergite with lateral projections; tergite IX with 6–9 setae (Neotropics)...... P. yanomani Spies, Fittkau & Reiss, 1994

- Anal tergite without lateral projections; tergite IX with more than 10 setae...................................... 45

45(44). Longitudinal band weakly present; anal tergite with 11 setae (Neotropics)......... P. manaos Spies, Fittkau & Reiss, 1994

- Longitudinal band absent; anal tegite with 15–25 setae (Neotropics)............... P. osa Spies, Fittkau & Reiss, 1994

46(36). Anal tergite V or Y type; superior volsella stout, with consecutive folds apically (Neotropics)............................................................................................ P. atroari Spies, Fittkau & Reiss, 1994

- Anal tergite band separated; superior vosella stout distally with pubescent expansion (Neotropics)................................................................................. P. lupus Trivinho-strixino, Silva & Roque, 2010

47(34). Gonostylus basally wide; superior volsella clubbed and curved outward (Australasia)...... P. delinificus ( Freeman, 1961a)

- Gonostylus pre-apically wide; superior volsella nearly straight with little wide apex.............................. 48

48(47). Anal point broad with rounded apex; superior volsella more or less spoon shaped (Neotropics)........................................................................................... P. matapi Spies, Fittkau & Reiss, 1994

- Anal point slender with apically widened apex; superior volsella variably developed.............................. 49

49(48). Superior volsella pediform distally; caudal region with lateral protrusion (Neotropics)............ P. vistosus Paggi, 1979

- Superior volsella apically sinuate; caudal region without lateral protrusion...................................... 50

50(49). Anal tergite band Y type; longitudinal band present; anal tergite with circular cushion like structure covered with microtrichia at ventral (Neotropics)........................................................ P. puberulus ( Edwards, 1931)

- Anal tergite band separated; longitudinal band absent; with a low basal lobe present at about midpoint of stem of anal point (Neotropics)......................................................... P. ticuna Spies, Fittkau & Reiss, 1994

51(29). Gonostylus medially and sub-apically little constricted (Nearctic)....................... P. abortivus (Malloch, 1915)

- Gonostylus not with above combination................................................................ 52

52(51). Gonostylus widened apically or sub-apically............................................................. 53

- Gonostylus nearly tapered or parallel shaped............................................................. 55

53(52). Superior volsella apically little sinuate; anal point with a conical tip of anal tergite at its base (Holarctic)................................................................................... P. monochromus (van der Wulp, 1874)

- Superior volsella digitiform; anal point without conical tip.................................................. 54

54(53). Gonostylus with disto-dorsal hump; anal point straight, originated from caudal margin of anal tergite (Neotropics)........................................................................... P. cayapo Spies, Fittkau & Reiss, 1994

- Gonostylus strongly clubbed distally; anal point curved downwardly, originated from cone shaped projection of tergite IX (Afrotropics).................................................................... P. lewisi ( Freeman, 1957)

55(52). Superior volsella straight............................................................................. 56

- Superior volsella curved............................................................................. 61

56(52). Superior volsella with a small beak-like projection at apex; anal point basally and apically constricted (Orient)................................................................................................. P. salsus sp. n.

- Superior volsella variably developed; anal point slender or tapered........................................... 57

57(56). Distal setal pit of superior volsella covering entire surface; setal pits different in size (Nearctic)................................................................................................. P. chaetaolus ( Sublette, 1960)

- Setal pits on superior volsella nearly equal in size......................................................... 58

58(57). Anal tergite band not meet medially; anal point slender (Nearctic)......................... P. elodeae ( Townes, 1945)

- Anal tergite band either V or Y type; anal point tapered or slightly widened apically.............................. 59

59(58). Anal tergite band V type; longitudinal band absent (Oriental China)........................................................................................... P. poyanjensis Yan, Yan, Jiang, Guo, Liu, Ge, Wang & Pan, 2015

- Anal tergite band Y type; longitudinal band present....................................................... 60

60(59). Anal point widened distally; gonostylus with basal constriction (Nearctic, Neotropics)...... P. supparilis ( Edwards, 1931)

- Anal point tapered distally; gonostylus without basal constriction; superior volsella with extensive median lining of microtrichia (Nearctic)........................................................... P. danicus Lehmann, 1970

61(55). Superior volsella curved outwardly (Afrotropics)..................................... P. sinuatus ( Freeman, 1957)

- Superior volsella curved inwardly...................................................................... 62

62(61). Tergite band not connected medially................................................................... 63

- Tergite band connected medially....................................................................... 64

63(62). Anal point rounded apically; anal tergite band Y type (Holarctic)....................... P. frequens ( Johannsen, 1905)

- Anal point somewhat spatulated; anal tergite band V type (Palaearctic)...... P. intermedius Zorina & Makarchenko, 2000

64(62). Gonostylus with distal shallow bending towards median part, its corner or angle situated beyond mid-gonostylus (Neotropics).................................................................... P. longistilus Paggi, 1977

- Gonostylus distinctly narrowing distally, its corner or angle of curving at about mid-gonostylus (Neotropics).......................................................................................... P. valdiviensis Spies, 2008