The descriptive text, below the map, is from the Cornish Red Data Book (2009). The map on this web page depicts the organisms distribution and shows the records made pre-2000 and those made since.
Range & Status
(Syn. H. suecica ). This species lives in fine, shelly, sub-littoral gravel and is known from only two localities in Britain, one off the Lizard Peninsula, the other in the Plymouth area. Elsewhere it is known from Roscoff, Brittany and the Mediterranean. It is probably much more common and widespread than supposed but is overlooked due to its very small size (1mm).
I.J. Bennallick, S. Board, C.N. French, P.A. Gainey, C. Neil, R. Parslow, A. Spalding and P.E. Tompsett. eds. 2009. Red Data Book for Cornwall and the Isles of Scilly. 2nd Edition.Croceago Press.
The Cornish Red Data Book Project was led by the Cornwall and Isles of Scilly Federation for Biological Recorders (CISFBR). The full text and species accounts (minus the maps) are available on the CISFBR website.