The polytene karyotype of a fewBilobella aurantiaca (Neanuridae, Collembola) Italian populations are described. The Southern populations show a smaller amount of α-heterochromatin than those of Central Italy. On the basis of recent views on heterochromatin significance, it is suggested that the Central populations might have a reduced frequency of chiasmata and be genetically more stable than the Southern populations. The differences in the band structure might reflect a cryptic speciation.