Scientific Name and Authority

Diplosoma aff. spongiforme   (Giard, 1872)


Diplosoma aff. spongiforme is a colonial species forming extensive thick, tough, but soft and loosely attached sheets. It grows on rock faces and associated fouling organisms, but rarely on algae. Colonies are ~6 mm thick and can occupy up to 0.25 m2. They are grayish-white in color, and may contain white non-calcareous bodies, while the zooids have black speckles. The tunic is more opaque than that of D. listerianum. The surface and basal test of the colony are connected by strands which enclose the zooids in clusters of 4-6 around a parent zooid. Zooids are ~ 1.5 mm long. The atrial opening is large. The ovary contains a single egg at a time. The larvae are large, with a trunk 0.6-8 mm long, 3-8 fixatory papillae and 2-7 pairs of ampullae (LaFargue 1975; Hayward and Ryland 1990). The wide range in papilla and ampulla numbers indicates that several species may have been combined in the authors' descriptions (Gretchen Lambert, personal communication 2012).

Taxonomic Classification:

Kingdom: Animalia
Phylum: Chordata
Subphylum: Tunicata
Class: Ascidiacea
Order: Aplousobranchia
Family: Didemnidae
Genus: Diplosoma
Species: aff. spongiforme


Astellium spongiforme (Giard, 1872)

Diplosoma chamaelon (Von Drasche, 1883)

Lissoclinum cupuliferum (Kott, 1952)

Diplosoma cupuliferum (LaFargue, 1968)

Potentially Misidentified Species:

Diplosoma listerianum