Cytogenetic aspects of the phylogeny of the genus Chironomus Meigen (Diptera, Chironomidae)

摘要

A phylogram was created for 94 species of the genus Chironomus on the basis of an integrated comparative analysis of the banding pattern of the chromosome arms A, E, and F. It is shown that the tendency toward inversion polymorphism in the arms studied is associated with formation of cytocomplexes. Evidence in favor of the ancestral nature of the thummi cytocomplex is presented. The evolution of larval forms from salinarius to plumosus form is hypothesized; species of the fluviatilis, semireductus,and reductus forms are represented only by terminal branches, originating from the thummi (fluviatilis) and plumosus (semireductus and reductus) forms. The ancestor of Ch. piger and Ch. riparius probably belonged to the pseudothummi cytocomplex, and thechromosome arm combination characteristic of these species (AB CD EF G) has secondarily originated from the AE BF CD G combination. Species of the riihimakiensis and pilicornis groups are not directly linked in the phylogram, which suggests their remoteaffinity.