Description: Thallus of microscopic branched filaments creeping between the cells of Zostera or shells. Hairs absent.

Habitat: Rare. Within the leaves of Zostera, clalk cliffs or periwinkle shells. In the lower and sublittoral.

Distribution: Recorded from shores all around the British Isle including the Shetlands. Europe: France, Baltic Sea and Norway. Atlantic coast of North America: Canada, Maine, New Hampshire and Massachusetts.

Similar Species: Microscopic examination required for identification. Possibly two entities may be confused under this name.

Distribution Map from NBN: Entocladia perforans at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Entocladia perforans at iNaturalist World Species Observations database.

WoRMS: Entocladia perforans at World Register of Marine Species.