Stolonica socialis is a colonial ascidian of 2 cm high. Up to 300 zooids can be closely
connected through a basal stolon to compose a colony. Zooids are ovoid, the test is smooth and its color may
vary from brown to yellow-orange. Siphons are terminal, prominent and small, the oral one being slightly
larger than the atrial one.
The colony is attached to rocks between 5 to 35 meters deep. It is found in the Atlantic Ocean from the
British coasts to Brittany and in the English Channel.
Phylum Chordata, subphylum Tunicata, class Ascidiacea, order Stolidobranchia, family styelidae, Stolonica socialis (Hartmeyer, 1903).
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.
Photograph: © Wilfried Bay-Nouailhat. Published With author's kind permission.
Stolonica socialis, Iles Glénan, South-Brittany, West of France. Depth 9 meters.
Text: Anne Bay-Nouailhat © 2005-2008.
Translation: Anne Bay-Nouailhat © 2007-2008.
