Dumontia contorta is a relatively small epiphytic algae of the sea-shore.
Description The thallus grows from a discoid holdfast to a length of about . The fronds branch irregularly and sparingly.Jones, W.E. 1964. A key to the genera of the British seaweeds. Field Studies 1 no.4:1 - 32 The branches are hollow, soft and twisted, dark reddish brown in colour which bleach towards the tips, they clearly taper at their junction.
Reproduction The plants are dioecious (sexes separate) with microscopic spermatangia, carposporangia, and tetrasporangia developing in the surface layer, cruciate.Bunker, StP, P, Brodie, J.A., Maggs, C.A. and Bunker, A.R. 2017 Seaweeds of Britain and Ireland. Second Edition, Wild Nature Press, Plymouth, UK.
Habitat Generally epilithic in rock pools of the littoral zone.
Distribution Common around the British Isles. Europe from Russia to Portugal and Canada to United States. In the NW Pacific and Alaska.Morton, O. 2003. The marine macroalgae of County Donegal, Ireland. Bulletin of the Irish Biogeographical Society No. 27 pp.3 - 164
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