SOMATIC CHROMOSOMES OF HIGHER DIPTERA: III. INTERSPECIFIC AND INTRASPECIFIC VARIATION IN THE GENUS HYLEMYA

Abstract

Analyses of the somatic complements of Hylemya antiqua, H. brassicae, H. cilicrura, H. crucifera, H. floralis, H. fugax, H. planipalpus, and H. trichodactyla (?) have been made following techniques described in the first paper of this series. All species, except H. fugax, have 12 chromosomes. These 12-chromosome species fall naturally into three main groups differing in average arm ratios and in other respects. H. fugax males have 13 chromosomes and females have 14, both including five pairs of submetacentric autosomes. One to three supernumerary chromosomes were found in a few larvae of H. cilicrura. Small intraspecific differences were found between collections of H. brassicae from different geographic locations. The results with this genus emphasize the inaccuracy of referring to complements which look similar as the same or identical.