Green barrel sea squirt

Didemnum molle · The green barrel sea squirt is a colonial tunicate that lives in the Red Sea and the tropical Indo-Pacific.

Also called Tall urn ascidian, Green reef sea-squirt.

Green barrel sea squirt
Photo: Silke Baron, CC BY 2.0
Green barrel sea squirt
Photo: Diego Delso, CC BY-SA 4.0
Green barrel sea squirt
Photo: Diego Delso, CC BY-SA 4.0

Taxonomy

KingdomAnimalia
PhylumChordata
ClassAscidiacea
OrderAplousobranchia
FamilyDidemnidae
GenusDidemnum
SpeciesDidemnum molle

Where it lives

Shallow reefs of the Red Sea and the tropical Indo-Pacific.

Fun facts

  • Its green colour comes from tiny blue-green algae living inside its body.
  • Its body has a built-in sunscreen that filters out ultraviolet light and protects its algae partners from strong sunlight.
  • It oozes so much mucus that it feels sticky to the touch.
  • Each urn-shaped individual can grow up to 10 cm across.

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Facts and taxonomy adapted from Wikipedia (CC BY-SA 4.0).