Catenella caespitosa is a small red marine alga.
This small alga grows to 20 mm high from a discoid holdfast and dark brown in colour. Very irregularly branched, creeping moss-like and terete. Branches easily seen to be constricted at intervals. Medulla, the inner cells, formed of thick-walled filaments and with a cortex of rows of elongated cells radially arranged compact cells.[1][2]
Catanella caespitosa occurs in shaded sites on rock and around the holdfasts of the fucoids of the upper littoral.[3]
Recorded around the British Isles, from Norway to the Mediterranean and further from the Indian and Pacific Oceans.[1]
The alga is monoecious, that is both male and female parts to be found on the same plant.[1] The spermatangia, the male gametes, and carposporophytes, the diploid phase, grouped together in sori. Tetrasporangia occur scattered towards the tips of the filaments of separate plants.[4]
Catenella caespitosa is a small red marine alga.
