Psen longula TOURNIER 1899; Psen simplex TOURNIER 1899
There are approximately 100 species in this genus worldwide. Lomholdt (1984) states that there are only seven species in Europe, but Bitsch et al. (2001) list ten, although one of these, P. hidalgo, was only described in 1990. Three species have been recorded in Britain. Psenulus schencki is the least often recorded.
This is the most rare of the three British Psenulus species, being restricted largely to the south-east, with scattered records from the south Midlands and Dorset. Falk (1991) additionally lists Essex and Cambridgeshire.
It is found across central and northern Europe and northern Africa and has been recorded at 1600m above sea level in the Alps (Bitsch et al. 2001).