Psen ambiguus SCHENCK 1857; Psen intermedius SCHENCK 1857
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.
This species has been widely recorded from south-east England, with more scattered records from the south-west, the Midlands, south and east Wales northwards to Yorkshire.
Lomholdt (1984) states that this species is rather uncommon and sparsely distributed in Scandinavia, but is widespread across northern and central Europe and also occurs through southern Siberia into Japan.