An erect bryozoan (Bugulina flabellata)

Distribution data supplied by the Ocean Biodiversity Information System (OBIS). To interrogate UK data visit the NBN Atlas.Map Help



Bugulina flabellata forms an erect, densely tufted, branched colony about 2-5 cm in height and is a buff colour when living, grey when dried. The branches are broad, flat and wedge-shaped, and composed of rows of four or more zooids, somewhat circularly disposed. Individual zooids are rectangular in shape and 0.5-0.8 x 0.2 mm. Zooids at the margin of the branches bear 3 spines on the outer distal corner and 2 on the inner distal corner. Inner zooids bear 2 spines on each distal corner. The front of the zooid is almost entirely membranous. The polypide has 14 tentacles. Avicularia are present on inner and marginal zooids, being larger on the latter, with the beak hooked rectangularly. Brood chambers (ooecia) are sub-globular and conspicuous. Colonies are attached to the substratum by extensions of the basal zooids termed rhizoids. Yellow embryos are present from early May to October. The newly settled larvae form ancestrula with 3 proximal spines and 3 spines on each distal angle.

Recorded distribution in Britain and Ireland

Relatively common around the coast of Britain. Records are more abundant on the east coast of Ireland than the west coast.

Global distribution

Extends from the North of Scotland to the Mediterranean.


Occurs on the lower shore and shallow sublittoral rocky shore. Usually attached to other bryozoan species such as Porella concinna, Schizomavella auriculata, Schizomavella linearis and Cellepora pumicosa, as well as the fronds of Flustra foliacea and the lobes of Alcyonidium diaphanum.

Depth range


Identifying features

  • Colony erect, branching and attached by frontal, lateral and basal rhizoids.
  • Colony 2-5 cm in height.
  • Branches are broad, flat and wedge-shaped, arranged somewhat circularly.
  • Buff colour when living, grey when dried.
  • Marginal zooids bear 3 spines on outer distal corner, 2 spines on inner distal corner.
  • Inner zooids bear 2 spines on both distal corners.
  • Ancestrula has 3 proximal spines and a further 3 spines on each distal corner.
  • Polypide has 14 tentacles.
  • Ooecia are sub-globular and conspicuous.

Additional information

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Listed by

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  2. Hayward, P., Nelson-Smith, T. & Shields, C. 1996. Collins pocket guide. Sea shore of Britain and northern Europe. London: HarperCollins.

  3. Hayward, P.J. & Ryland, J.S. (ed.) 1995b. Handbook of the marine fauna of North-West Europe. Oxford: Oxford University Press.

  4. Hayward, P.J. & Ryland, J.S. 1998. Cheilostomatous Bryozoa. Part 1. Aeteoidea - Cribrilinoidea. Shrewsbury: Field Studies Council. [Synopses of the British Fauna, no. 10. (2nd edition)]

  5. Hincks, T., 1880. A history of British marine Polyzoa, vol. I & II. London: John van Voorst.

  6. Howson, C.M. & Picton, B.E., 1997. The species directory of the marine fauna and flora of the British Isles and surrounding seas. Belfast: Ulster Museum. [Ulster Museum publication, no. 276.]

  7. JNCC (Joint Nature Conservation Committee), 1999. Marine Environment Resource Mapping And Information Database (MERMAID): Marine Nature Conservation Review Survey Database. [on-line]


  1. Fenwick, 2018. Aphotomarine. Occurrence dataset Accessed via on 2018-10-01

  2. NBN (National Biodiversity Network) Atlas. Available from:

  3. OBIS (Ocean Biodiversity Information System),  2024. Global map of species distribution using gridded data. Available from: Ocean Biogeographic Information System. Accessed: 2024-07-14


This review can be cited as:

Ballerstedt, S. 2004. Bugulina flabellata An erect bryozoan. In Tyler-Walters H. and Hiscock K. Marine Life Information Network: Biology and Sensitivity Key Information Reviews, [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 14-07-2024]. Available from:

Last Updated: 29/07/2004