Aquatic invasive species

DIPLOSOMA

(Diplosoma listerianum)

Diplosoma is an invasive colonial tunicate primarily seen in tropical and temperate waters. This species probably originates from northern Europe and has spread along the American east coast. This tunicate was first observed in eastern Canada on the Magdalen Islands in 2008.

HABITAT

See the habitat of the tunicates

Diplosoma – M. Desraspes
M. Desraspes

CHARACTERISTICS

Diplosoma – R. Groeneveld
R. Groeneveld
  • Dense colonies that are soft, gelatinous and translucent;
  • Forms fragile crusts which are hard to remove without tearing;
  • Colour : darkish grey;
  • Openings sometimes spotted with white dots.

SIMILAR SPECIES

Alcionidium – DFO I. Bérubé
Alcionidium
DFO I.  Bérubé

Diplosoma may resemble certain types of sponges, but their texture is gelatinous rather than spongy.

Diplosoma may also be mistaken for Alcionidium, but this native bryozoan does not have the characteristic openings of tunicates.

Sponge – DFO R. Larocque
Sponge
DFO R. Larocque

ECOLOGICAL AND ECONOMIC IMPACTS

See the impacts of the tunicates
Diplosoma – M. Desraspes
M. Desraspes

WHAT YOU CAN DO