Kingdom Animalia Class Ascidiacea Phylum Chordata Rank Species | Subphylum Tunicata Family Ascidiiae Genus Phallusia Order Enterogona | |
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Similar Phallusia, Ascidiidae, Herdmania, Microcosmus, Polyclinum | ||
Ascidian embryonic development phallusia nigra tunicata ascidiacea
Phallusia nigra is a solitary marine tunicate of the ascidian class found in tropical seas around the world. It usually lives in shallow waters, attached to any hard substrate.
Like all tunicates, P. nigra has a thick leathery envelope (tunic) containing cellulosic material. Like all solitary ascidians, the tunic encloses a sac-shaped body with separate water entrance and exit tubes (siphons). It lives on plankton that it filters from seawater with a mucous net.
An adult P. nigra may be 10 centimetres (3.9 in) long. The tunic is usually velvet black or dark brown, but may be gray in specimens that are younger or live in shaded areas. Its original range is unclear; the tropical Western Atlantic Ocean, the Red Sea, and the Indian Ocean have been proposed.
The tunic of P. nigra contains many vesicles filled with a strong acid (with pH near 1), containing mostly sulphate SO
42− and chloride (Cl−
) anions. The vesicles are concentrated towards the outer surface and are easily ruptured by contact; they are believed to protect the animal from predation and fouling.
Substances extracted from the dried tunic with methanol have been found to have cytotoxic, antibacterial, antipyretic, analgesic, and histamine-like activity.