Alcyonidium condylocinereum

General description: 

This species grows as erect colonies, often with knobbly protuberances.  Latin: condylus, knob; cinereus, grey


Colonies grow as erect, gelatinous structures, adherent to the seabed or to shells and small boulders.

Look alikes: 

This species looks similar to Alcyonidium diaphanum but it is grey in colouration rather than honey-brown.


The holotype is BMNH 2002.2.1.3 from the Dover Strait, English Channel 50.65°N, 01.51°E. Colonies are grey and have a knobbly appearance. The knobs measure about 0.5mm in diameter and stick out 2.3 mm from the colony surface. The colony has a central column with branches growing from the column at intervals along its length. Part way along its length the colony splits into two stout branches, further branches then emanate from these.


The holotype (BMNH 2002.2.1.3) colony measures 8x4.5x1 cm and the paratype (BMNH 2002.2.1.4) measures 6.5x4.5x1 cm. This species is under recorded so little is known about the full extent of colony size.


This species has been distinguished from Alcyonidium diaphanum on the basis of mitochondrial gene sequences (12s and COI).


This species has been recorded from the southern North Sea, English Channel and Bristol Channel. There are very few published records of the species. It can be found from the LWST level down into the shallow sublittoral.


Histological examination has shown the presence of numerous small oocytes during the development of the ovary. The presence of an intertentacular organ has also been observed. These strategies are usually associated with species that broadcast their larvae.

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith