The salivary gland chromosomes of Chironomus oppositus Walker (Diptera : Nematocera)

Abstract

Chromosome maps for C. oppositus, which are intended to serve as a standard for the genus Chironomus in the Australasian region, are presented. This species possesses the usual four salivary gland chromosomes and the seven arms, named A-G by Keyl (1962), can be recognized. This species has the combination AE, BF, CD, G, corresponding to the pseudothummi group of Europe. The relationship of C. oppositus to European species of the pseudothummi group is not definite as an independent origin of this arm combination is possible. The species is quite polymorphic, 13 inversions having been recognized. The limits of these inversions, with preliminary data on their distributions, are given.