Trididemnum cerebriforme

Hartmeyer, R 1913
Phylum Chordata
Class Ascidiacea
Order Aplousobranchia
Family Didemnidae
  • Colonial ascidian form large three dimensional elaborate folded hemi-spherical masses.
  • Surface free of foreign particles and epibonts.
  • Zooid arranges in elaborate system around a large common cloacal opening.
  • Colonies are firm and resilient, with spicules distributes within the test providing firmness and responsible for the white speckled appearance especially visible in darker pigmented colonies.
  • Spicules stellate with sharp rays.
  • Atrial opening may be short or long tube-like siphon depending on the position in the test.
  • Retractor muscle extends from the posterior of the thorax.
  • Branchial sac with 3 rows of 8-10 stigmata.
  • Large testis follicle is covered by 7-9 spiral coils of the sperm duct, male and female gonads develop consecutively.
  • Larvae may vary in size and has three adhesive papillae and a variable number (4-8 depending on the developmental stage) laterally ampullae.
© 2010 Shirley Parker-Nance 2010-10-04 21-26-48_0116.JPG

  • Hartmeyer, R 1913 Zoologische,und antropologische Ergebnisse eine for schungsreiese im westlichen un zentralen, sudafrica : Tunicata.5:125-144
  • Monniot, C.; Monniot, F.; Griffiths, C. and Schleyer, M. 2001 Ascidians of South Africa.108:1-141
  • Shenkar, N.; Gittenberger, A.; Ruis, M.; Rocha, R. M.; Swalla, B.; et al. 2017 Ascidiacea World Database. Atriolum marinense Kott, 2001. Accessed through: World Register of Marine Species at: on 2019-03-12