Analisi cariologica di tre specie di Onichiuridi (Collembola, Insecta)
The chromosomes from 3 species of Collembola Onychiuridae belonging to the same genus, Onychiurus (Protafthorura), were analyzed. Onychiurus armatus and Onychiurus glebatus, with the highest chromosome number in Collembola (2n = 18), have morphologically different karyotypes. The diploid chromosome number of Onychiurus quadriocellatus is 2n = 16. There are not numerical differences between the two sexes. The taxonomic and evolutive significances of the unusual numerical differences within a collembolan...