Thick encrusting (2 -3 cm thick) of folded gelatinous masses (20 cm in diameter).
Zooids (2-3 mm long) arranged in elaborate meaning systems.
Branchial opening with very short siphon, atrial opening with large languet and slit-like aperture.
Zooids with gut loop along the posterior side of the branchial sac.
Branchial sac with 12-14 rows, with 2-3 stigmata between longitudinal vessels.
Stomach with 8-10 longitudinal folds.
Larvae (0.5 mm) in length with 8 ampullae.
References
Monniot, C. and Monniot, F. 1997 Records of ascidians from Bahrain, Arabian Gulf with three new species.31:1623-1643
Monniot, F. and Monniot, C. 1997 Ascidians collected in Tanzania.86:1-35
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: http://www.marinespecies.org/aphia.php?p=taxdetails&id=250052 on 2019-03-12