Larva of thummi-type. Head with dark gular region and dark head stripe on the frontoclypeus. Centre tooth of mentum moderately wide with c2 teeth well separated (type II).
Cytology: 4 pairs of chromosomes with the thummi-cytocomplex arm combination (AB, CD, EF, G). Centromeres heterochromatic. Arm G often unpaired, with a subterminal nucleolus after a heterochromatic terminal band, and an apparently heterochromatic interstitial band. At least one BR, but not clear enough to be sure if others are developed. Polymorphism in arms A, D and F in the Palearctic, but presently only arm F known to be polymorphic in North American populations. However, arm A seems to be the sequence A3, which is less common in the Palearctic. The karyotype is based on identifications by Kiknadze et al. (1996 & 2004).
h'jom A3: 1-2c, 10-12, 4-5, 3-2d, 9-6, 13-19 i.e. as Wülker 1991b.
h'jom B1: 1-7, 8b-15, 22-28 - according to Hirvenoja & Michailova (1997), but this leaves many
bands unaccounted for.
h'jom C1: 1-6b, 11-8, 15-11d, 6gh, 17a-16, 7d-a, 6f-c, 17b-22 according to Kiknadze et al., 2004
h'jom D1: 1-3, 11-18d, 7-4, 10-8, 18e-24 i.e. as Kiknadze et al., 2004.
h'jom E1: 1-3e, 5-10b, 4-3f, 10c-13 i.e. as aberratus, plumosus E1, etc.
h'jom F1: 1-10, 17-11, 18-23 i.e. as cucini, tenuistylus, etc.
h'jom F3: 1-2, 5-3, 6-10, 17-11, 18-23 from Kiknadze et al., 1996b
Click here for the polytene chromosomes
Found: North West Territories – tundra pond FBV, Horton river area (M.G.Butler)
C. jonmartini was proposed by Lindeberg & Wiederholm as a new name for C. neglectus Lindeberg. It is not clear that the present material is identical to that of Lindeberg & Wiederholm, which was partly cytologically described by Wülker (1973, 1991b). That material from Fennoscandia had a plumosus-type larva, and arm G may differ. However, studies from other parts of the Palearctic indicate that the larval morphology and chromosomal banding patterns are variable (Kiknadze et al. 1996b, Rakisheva et al. 2001). The North American material seems to be identical to that described by Kiknadze et al. (1996b).