1. Larva a salinarius-type. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
        Larva with at least some development of ventral tubules. . . . . . . . . . . . . . . . . . . . .6

    2. More than 60 striations on Ventromental plate. . . . . . . . . . . . . . . . .C. zealandicus (= C. species a)
        Less than 60 striations on Ventromental plate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

    3. Anal tubules relatively long sometimes with slight constriction near middle . . . . . .C. forsythi
        Anal tubules relatively short, pointed or rounded. . . . . . . . . . . . . . . . . . . . . . . . . . . .4

    4. Frontoclypeal region of head only slightly darkened, centre tooth (C1) of mentum broad. . . sp.9
        Not in North Island.
        Frontoclypeal region very dark, C1 tooth of mentum broad or narrower. . . . . . . . . . . .5

    5. C1 tooth of mentum broad. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C. 'castaneum'
        Not in North Island.
        C1 tooth of mentum generally narrower. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C. analis

    6. Slight development of posterior ventral tubules only. . . . . . . . . . . . . . . . . . . . .C. 'thermarum'
        In thermal waters (but C. zealandicus/species 10 and sp. 12 can be also)
        Two pairs of ventral tubules present. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

    7. Anal tubules relatively long, as in C. forsythi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .sp.8
        Anal tubules shorter and rounded. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

    8. Head somewhat narrower, ratio mentum width/VHL less than 0.65 . . . . . . . C. novae-zelandiae
        with frontoclypeus generally darkened but sometimes pale or only slightly darkened
        (which group would include C. 'spilleri'; sp. 11; and sp. 12)

      Head broader, ratio mentum/VHL above 0.65 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . sp.7
        with darkened frontoclypeus. Not in North Island.

In the following descriptions, reference is made to the mentum and mandible types as described for European Chironomus species by Webb & Scholl (1985) and Vallenduuk & Moller Pillot (1997)
The mentum type is defined only by the degree of development of the 4th lateral teeth:
Type I - height in same line as the rest of the lateral teeth;
Type II - 4th laterals reduced, height about equal to that of the 5th laterals;
Type III - 4th laterals further reduced, height less than that of the 5th laterals.

The mentum may be further classified by the characters of the central trifid tooth:
Type I - C2 teeth only partially separate from C1, i.e. as shoulders on C1.
Type II - C1 broad, C2 teethdistinctly separated.
Type III - C1 tooth relatively narrow and much higher than the separated C2 teeth.
Type IV - C1 tooth relatively narrow, but only slightly higher than the separated C2 teeth

The mandible type is defined by the degree of darkening and separation of the 3rd inner tooth:
Type I - 3rd tooth pale and almost completely fused on lower margin;
Type II - some degree of pigmentation and tooth partly free on lower margin;
Type III - 3rd tooth as dark as other inner teeth and completely separate.

Chironomus zealandicus Hudson, 1892

There have been several attempts to relate C. zealandicus to one of the cytologically known species, and it has been suggested at different times that it was either species 1 (Forsyth,1978 and Martin,1998) or C. species a (Martin,1996).
However, species 1 can be ruled out because there is an entry in Hudson's journal that he reared the specimens of C. zealandicus from larvae without ventral tubules. Forsyth therefore thinks that C. species a is the species that corresponds to Hudson's C. zealandicus. This is supported further by the fact that C. species a is the largest of the reared species, about the size of Hudson's C. zealandicus specimens.
The name is therefore used in this sense in this work.

Chromosome banding patterns ahve been published using the Australian standard system of Martin (1964), but are in process of being switched to the more universally used (although more difficult to uniquely specify bands) system of Keyl (1962) and Devai et al. (1989).

7. Chironomus n.sp.

Larval Morphology: bathophilus-type larva, although ventral tubules shorter than C. novae-zelandiae. (about 0.5 - 1 mm).    Medium size species, about size of C. forsythi and C. analis, length about 16 - 19 mm.    Head capsule relatively broad, width of mentum at least 2/3 of VHL; generally with a darkened frontoclypeus, and sometimes in surrounding regions, with gular region dark.    Mentum with 4th laterals slightly reduced, sometimes higher than 5th laterals (i.e between type I & II), c1 tooth relatively broad, c2 teeth usually separated, but occasionally still partially on shoulders of c1 (i.e. usually type II, but sometimes still type I).    Ventromentum with about 43 - 46 striae.    Antennae with basal segment at least 3.5 to 4.4 times as long as wide; AR about 1.8 - 2.3.    Pecten epipharyngis with 11 - 17 teeth, some of which are reduced in size.    Mandible of type II, with about 24 - 26 striae near the base.

Cytology: 4 polytene chromosomes with unique chromosome arm combination (BG, CD, EA, F).
One large nucleolus proximal on arm G.    Arm A differing from A2 of C. forsythi by Inv14B-14C; arm E as E1 of Australian species; arm F as oppositus F3, australis, etc.

Arm A1: (approx) 14A, 14C-14B, 15E1, 15D-15C, 14D9, 15B-14D10, 15E2-10
Arm B1:    Puff (group 7) with proximal dark bands (group 8) near middle of arm.
Arm C1:
Arm D1:
Arm E1:    1 - 3e, 10b - 3f, 10c - 13                            ie. as E1 oppositus
            (12A - 13D)
Arm F1:    1 - 2a, 10 - 2c, 15c - 11a, 2b, 15d - 23            ie. as F1 of novae-zelandiae, oppositus F3, australis
            (4A-5B1, 5D2-5B2, 5D3-6D)
Arm G1:

Click here to see the polytene chromosomes

Known Localities

The unique chromosome arm combination was noted by Wülker & Morath (1989)

9. Chironomus n.sp.

Larval Morphology: salinarius type larva, length c.13-15mm.    Head capsule with gular region darkened, frontoclypeus very slightly to slightly darkened, but with some darkening of the posterior border of the frontoclypeus.    Mentum essentially type II (4th laterals slightly reduced, but may still be above level of 5th laterals); centre tooth of type II.    Ventromentum with about 36-40 striae.    Pecten epipharyngis with about 14 - 15 relatively even teeth.    Antenna with basal segment about 3.25x as long as wide; fourth segment about 1.6x length of 3rd.    Mandible of type II, with about 18 - 22 striae near the base.
Gut of most larvae almost filled with sand particles.

Cytology: 4 polytene chromosomes with thummi cytocomplex arm combination (AB, CD, EF, G).
    Centromeres heterochromatic.    Two nucleoli, one proximal in arm F; the other about one third from the heterochromatic end of arm G.    A Balbiani ring developed near distal end of arm G.    Arm A with the sequence A4 found in Australian species; arm E with sequence E1 of the Australian species; and arm F as in C. oppositus F3 and C. australis..    No polymorphism in the small sample examined.

Arm A1:    1a-e, 11-10, 2c-1f, 3e-2d, 8-9, 3f-i, 12c-a, 4-7, 13-19                 ie. as A4 oppositus             (14A-14D8, 15E1, 15D-15C1, 14D9-15B, 15E2-10)
Arm B1:    Puff (group 7) and about 2 dark bands (8ab) distal, close to 4 characteristic bands.
Arm C1:    possibly 10A-10D6, 11B11-10D7, 11B12-11E;     ie. as C2 of forsythi
Arm D1:
Arm E1:    1 - 3e, 10b - 3f, 10c - 13                            ie. as E1 oppositus, analis
            (12A - 13D)
Arm F1:    1 - 2a, 10 - 2c, 15c - 11a, 2b, 15d - 23            ie. as F3 of oppositus, and F1 of australis and forsythi
            (4A-5B1, 5D2-5B2, 5D3-6D)
Arm G1:

Click here to see the polytene chromosomes

Localities:
South Island:
    Lake Hayes, c.13km n.e. Queenstown, Westland (NZ.47.1) (Jon Martin) 7-i-1974