This is probably a very common throughout Britain and Ireland but unfortunately most records are not differentiated between the two species (simply given as T. pusillus agg.). Verified records (based on male specimens) indicate a wide distribution throughout Britain and Ireland, but it seems more common in areas where calcareous strata occur.

It favours sunnier and/or drier situations than Trichoniscus pusillus s.str., including semi-natural limestone grassland, free-draining woodland and domestic gardens, where it can be found under stones, dead wood, etc.

This summary is based on the detailed account in Gregory (2009).