Hydraena pygmaea

Range & Status

Primarily western in distribution from Cornwall to Aberdeenshire, with an outlying record for Sussex. There are very few modern records. Foster (1990) provides a national distribution map.

Regional Distribution

Two records by the author: from the River Kenwyn in 1980 and a small stream at Trebudannon in 1981. Found in the West Looe River by Adrian Brown in 2004.

Habitat & Ecology

Under stones, in moss and on clods of clay in swift flowing, stony streams and rivers.


Pollution of water courses and river improvement schemes.