Pyura spinosa   (Quoy & Gaimard,  1834) (Sea Squirt)
Organism information awaits expert curation
Class: Ascidiacea

Image copyrights: The Marine Biological Association of India

Size: 2.5 cm in height, 3 cm wide

Individual kidney shaped. Apertures at the anterior end, directed anteriorly, siphons not ridged. Branchial siphon slightly longer than the atrial siphon. Test tough, hard with small pointed tubercles distributed on both sides of the body but absent from around and on the siphons. Test with spherical calcareous spicules, siphon lining with minute pointed overlapping spines.

Body wall very thin. Strong longitudinal muscles from both siphons cross over to the sides of the body and form an irregular mesh over the posterior end of the body. Branchial tentacles have primary, secondary and tertiary branches but not very bushy. 16 larger tentacles with smaller ones in between. Prepharyngeal area narrow. Dorsal tubercle in the V-shaped peritubercular area, has a U-shaped slit directed anteriorly with one horn turned in. Dorsal lamina long, languets short and not crowded. Six branchial folds on each side with upto 19 internal longitudinal vessels on folds and 3 between them. Gut forms a J-shaped loop wide in its terminal half. 6 pairs of liver diverticula along the pyloric region of the gut, anal border with 6 short lobes. Central gonoduct with small rounded polycarps sacs, about 12-16 arranged on both sides and a terminal one. Sacs secured to the body wall. Left gonad entirely enclosed by the gut loop. Small endocarps present in the gut loop and on the free surface of polycarp sacs.

Synonym (s)
Ascidia spinosa Quoy & Gaimard, 1834
(Original combination)
Ascidie spinosa Quoy & Gaimard, 1834
(Incorrect original spelling)
Cynthia cataphracta Herdman, 1899
(Original combination)
Cynthia cataphracta Herdman, 1898
Cynthia cerebriformis Herdman, 1881
(Original combination)
Halocynthia cerebriformis (Herdman, 1881)
(New combination)
Pyura cataphracta (Herdman, 1899)
(New combination)
Pyura leeuwinia Kott, 1952
(Original combination)

Common Name (s)
Economic Importance and Threats

Habitat:  Demersal


• Tamil Nadu, Tuticorin Harbour (Lat: 8.8) (Long: 78.18) INDIA (Depth: -5 mts)

Literature Source(s)
  • Meenakshi, VK and Senthamarai, S (2006) First report of a simple ascidian - Pyura spinosa (Quoy and Gaimard, 1834) from Tuticorin Coast of India Journal of the Marine Biological Association of India The Marine Biological Association of India, Cochin 48(1) 103-104 Available at - NIO, Goa
  • Society for the Management of European Biodiversity Data (2009) World Register of Marine Species (WoRMS) Available at -
  • Sealifebase Available at -

Page last updated on:2010-08-24

Back to Search