A species with polytene chromosomes that are larger than those of Drosophila melanogaster and exceptionally favorable for cytological analysis. The virilis genome is one of the largest in the genus (313 mb). D. virilis and D. melanogaster are very distantly related, having diverged about 60 million years ago. The virilis karyotype is considered to be ancestral for the genus. Its chromosomes X, 2, 3, 4, 5, 6 correspond to the chromosome arms X, 3R, 3L, 2L, 2R, and 4 of Drosophila melanogaster. See Drosophila, Drosophila salivary gland chromosomes.
Subjects: Genetics and Genomics.