Diplosoma spongiforme is an encrusting colonial ascidian which can cover
rock surfaces of 20 to 30 cm in diameter. Several colonies can join together and can thus cover a surface
of several square meters. Zooids are immersed in a common gelatinous test. Its thickness is irregular, up to
6 mm , giving to its surface an embossed aspect. The oral siphons of the zooids constitute tiny openings densely
distributed all other the colony. Several zooids are gathered around a common, broad and slightly prominent
atrial siphon, forming a system. Several systems occur in the colony making it resemble a sponge. The
jelly-synascidian has a white translucent test with greenish or yellowish mottlings. The margin of the siphons
may be white or bluish.
It is present from surface to 40 m deep in the Atlantic Ocean, the English channel, the North Sea and the
Mediterranean Sea.
(source : European Register of Marine Species)
Zooid : Individual, single animal.
Test : or tunic: thick layer secreted by the mantel containing cellulose and protecting the animal.
Oral siphon : Opening by which water is drawn in the ascidian.
Atrial siphon : Opening through which water is expelled.
Diplosoma spongiforme
Colony
Diplosoma spongiforme
Diplosoma spongiforme
Detail
Top photograph :
© Wilfried Bay-Nouailhat. Published with author's kind permission :
Diplosoma spongiforme,
Iles Glénan, South Brittany, West of France. Depth 6 meters.
Bottom photographs : © Wilfried Bay-Nouailhat. Published with author's kind permission :
Diplosoma spongiforme, Colony. Iles Glénan, South Brittany, Wet of France. Depth 6 meters.
© Wilfried Bay-Nouailhat. Published with author's kind permission :
Diplosoma spongiforme, . Anse de Camaret, West-Brittany, West of France. Depth 6 meters.
© Wilfried Bay-Nouailhat. Published with author's kind permission :
Diplosoma spongiforme, Detail. Iles Glénan, South-Brittany, West of France. Depth 6 meters.
Text : Anne Bay-Nouailhat © 2005-2010.
Translation : Anne Bay-Nouailhat © 2007-2010.
