Larva a large salinarius or halophilus-type, i.e. posterior ventral tubules sometimes present. Gular region darkened posteriorly, frontoclypeus pale or slightly darkened with small dark stripe in posterior part and a lobed dark spot in anterior part. Mentum with relatively shallow curve, teeth pointed; centre tooth moderately broad, side teeth moderately separated; first laterals slope away from centre; fourth laterals definitely reduced.
Cytology
: 4 pairs of chromosomes with the thummi arm combination AB, CD, EF,
G.
Centromeres
very heterochromatic, forming a chromocentre with all chromosomes attached.
Arm G with nucleolus, bounded by dark bands, near centromere, then a
constriction
followed by two Balbiani rings which may be more obvious in
Californian populations.
No nucleolus in long chromosomes mostly but a nucleolus may be
developed in the
middle of arm B of some Californian specimens. No
inversion polymorphism has been observed.
cuc A1: 1 - 2c, 10 - 12, 3 - 2d, 9 - 4, 13 -19;
i.e. as holomelas,
tardus,
etc.
cuc C1: 1-6b, 15c-e, 8-11c, 15b-11d, 6gh, 17a-16, 7d-a,
6f-c, 17b-22 i.e. as islandicus,
sp. 3b.
cuc D1: 1 - 3, 11 - 18d, 7 - 4, 10 - 8, 18e - 24
ie. as longistylus, tardus, pilicornis,
etc.
cuc E1: 1 - 3e, 5 - 10b, 4 - 3f, 10 - 13;
i.e as
cingulatus, tardus
& sp. 3b.
cuc F1: 1 - 10, 17 - 11, 18 - 23;
i.e.
as in tenuistylus, major
& tardus.
Found: British
Columbia - Osoyoos (Townes
(1945) as C. atritibia)
Ontario - Clarke Lake, Kearney Lake, and
Costello Lake, Algonquin Provincial Park; Lake Nipissing(?)
Quebec - Manatek Lake; Mecantic(?)
Indiana - Crooked Lake
California - Lake Davis, Plumas Co.; Castle Lake,
Siskayou Co.
New
York - Kanisko Reservoir, Westchester County (Townes (1945) as C. atritibia)
Minnesota - Long Lake
Thick mud in depth 5 m or more in lakes.
Morphology described by Webb (1969), karyotype figured by Martin (1979) and described by Wülker & Butler (1983). This was Species 7 of Wülker.