Description: Erect tufts of 2 to 5 shoots rising from a discoid base, each shoot, attenuate at the base, to 25 mm or more long, uniseriate below and multiseriate above with short radial monosiphonous branches enveloping the axis.

Habitat: Rare. Epiphytic on Zostera and algae in lower littoral and upper sublittoral.

Distribution: Recorded in the British Isles from few scattered sites in west of Scotland, west of Ireland, south-west of England and Isle of Man. Europe: Spain, France and Norway. Atlantic coast of North America: Maine.

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

iNaturalist: Leblondiella densa at iNaturalist World Species Observations database.

WoRMS: Leblondiella densa at World Register of Marine Species.