Axinella agnata is an arborescent sponge from 8 to 15 cm in height. The branches are
regularly ramified and very often they have a y-shaped tip. The velvety surface is pale yellow. It is
attached to rocks, boulders and sometimes in cracks.
It is found from 10 to 40 m deep in the Atlantic Ocean and the English Channel.
Many erected species look similar; each have distinctive characteristics:
Axinella damicornis is fan-shaped.
Axinella dissimilispossesses small oscules surrouded by ridules forming a star.
Axinella egregia has a rough surface resembling a fur.
Axinella polypoides presents a diameter of the terminal ramifications sligtly tapering.
Phylum Porifera, class Demospongiae, order Halichondrida, family Axinellidae, Axinella agnata Topsent, 1896.
Oscule: Opening generally quite visible, through which sponges expel water they have filtered to extract food particles.
Photograph: © Wilfried Bay-Nouailhat. Published with author's kind permission.
Axinella agnata, Iles Glénan, South-Brittany, West of France. Depth 15 meters.
Text: Wilfried Bay-Nouailhat © 2004-2008.
Translation: Anne Bay-Nouailhat © 2007-2008.
