Karyotype and larva morphology of Chironomus oculatus sp n (Diptera, Chironomidae)

Chromosome arms combination of Chironomus oculatus sp.n. is AB CD EF G (thummii complex). Centromeres are heterochromatisated. Arm G has 3 Balbiani rings and one nucleoli, its homologes are partially conjugated (at 1/2-1/3 of the chromosome length). Arm mapping: A, C, D (incomplete mapped), E and F - according to Ch. piger standard (Keyl, 1962; Devai et al., 1989), B - according to Ch. plumosus standard (Shobanov, 1994). Arms A and E are identical to those in Ch. plumosus. In arm D there is a Balbiani ring. Chromosome CD in characterized by the complex perycentric restruction (compared with the piger standard), which is similar to structure of the near-centrometric region in the homeological chromosome of Ch. balatonicus. The body length of larvae is up to 16 mm, they have lateral tubules on VII abdomenal segment and ventral tubules on VIII abdomenal segment. The length of the latter is about equal to the width of segment VIII (f.l. semireductus or plumosus). The length of eyes is over 100 mm, the distance between them being a half of their length.