''Pyura spinifera'', commonly called the sea tulip, is a species of

sessile Sessility, or sessile, may refer to: * Sessility (motility), organisms which are not able to move about * Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant * Sessility (medicine), tumors and polyps that ...

ascidian Ascidiacea, commonly known as the ascidians or sea squirts, is a paraphyletic class in the subphylum Tunicata of sac-like marine invertebrate filter feeders. Ascidians are characterized by a tough outer test or "tunic" made of the polysaccharid ...

that lives in coastal waters at depths of up to 80 m (260 feet). As with almost all other ascidians, sea tulips are filter feeders. The common name comes from the organism's appearance - that of a knobbly 'bulb' or flower attached to a long stalk. Sea tulips come in a variety of colours, including white, pink, yellow, orange, and purple. The coloration of sea tulips depends upon their association with a

symbiotic Symbiosis (Ancient Greek : living with, companionship < : together; and ''bíōsis'': living) is any type of a close and long-term biolo ...

sponge Sponges or sea sponges are primarily marine invertebrates of the animal phylum Porifera (; meaning 'pore bearer'), a basal clade and a sister taxon of the diploblasts. They are sessile filter feeders that are bound to the seabed, and a ...

that covers their surface.

References

WoRMS

External links

Wildlife of Sydney - Sea Tulip
Pyuridae Animals described in 1834 {{tunicata-stub