North American Chironomus: C. tentans

Species 3y. C. tentans Fabricius.

Was placed in the subgenus Camptochironomus.

The adult and pupa of the Alaskan material have not been described.

On the assumption that it is possibly C. tentans, the illustration of the genital region of the female by Rodova (1978) is shown below.

Fourth instar larva a large plumosus-type. Gular region slightly darkened, with frontoclypeus darkened particularly in the center.

Cytology: 4 polytene chromosomes with the camptochironomus arm combination AB, DE, CF, G.
Arm G with 3 Balbiani rings. Nucleoli in arms B and D, as in Palearctic populations. Polymorphism in arms A, B, C, D, and F; males particularly are heterozygous for arm F.

ten h'A1: 1a-g, 7a-3i, 7b-8e, 17f-13, 1h-2c, 9c-8f, 10-9d, 11-12c, 3h-2d, 17g-19
ten h'A2:
ten h'B1:
ten n'B2:
ten h'C1: 1-2d, 11d-14c, 19f-16, 7-6c, 8a-g, 6b-4, 14d-15, 9-11c, 3-2e, 20-22
ten n'C2: 1-2d, 4g-6b, 9-11c, 3-2e, 11d-14c, 19f-16, 7d-6c, 8a-g, 15-14d, 4a-f, 20-22
ten n'C3(1Lz):
ten n'D1:
ten n'D2:
ten h'E1: 1-2b, 7h-10b, 3e-2c, 07g-3f, 10c-13
ten h'F1: 1a-d, 9b-12, 3b-2f, 13-14c, 5d-6, 9a-7a, 14d-16, 5c-3c, 1e-2e, 17-23
ten n'F2: 1a-d, 9b-12, 3b-2, 13a-d, 1i-e, 3c-5c, 16-14d, 7-9a, 6-5d, 14c-a, 2a-e, 17-23
ten n'F3(1Rjk):
ten h'G1:

Found: Alaska - Potters Marsh, Anchorage.

There is some doubt that this species actually occurs in North America. However the data of Acton (1962) suggests that Alaskan populations should still be considered as C. tentans.

See also C. dilutus and C. pallidivittatus

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