There are a few widely scattered records in the literature for Isotomurus palustris var. maculatus but it is now thought probable that it is a species in its own right. The dorsal pattern of Isotomurus maculatus is quite distinctive (Fig. 1) and it seems to be found mainly in sites associated with human activity. In The Netherlands, Matty Berg has found Isotomurus maculatus to be very common in gardens, heaps of dead leaves in car parks and against the walls of houses, small ridges between paving stones and other similar sites. In a garden in Reading, Isotomurus maculatus occurred among liverworts growing in the cracks between the stones of a shaded path. During periods of rain, Isotomurus palustris could also be found in the same habitat.
The map for Isotomurus palustris contains many literature records that should probably refer to Isotomurus maculatus before it was recognised as a separate species and not simply a colour variety of Isotomurus palustris.
There is an excellent web site on European Isotomurus by Antonio Carapelli and colleagues at the University of Siena [http://www.unisi.it/ricerca/dip/collemboli/isotopage/intro.htm]
Recently an Isotomurus maculatus - collected in 2013 from the gardens of Froebel college, Roehampton lane, London - had its COI molecular barcode sequenced, and proved to be 100% identical to a collection of Isotomurus maculatus from Marion Island in the sub-antarctic! Doubtless another example of western ships carrying accidental stow-aways.