The Echinoid Directory

Brissoma Pomel, 1888, p. 41

Diagnostic Features
  • Test ovate with shallow but distinct anterior sulcus. Depressed in profile.
  • Apical disc ethmolytic, with 4 gonopores. Madreporic plate projecting well behind the posterior ocular plates.
  • Anterior ambulacrum narrow and shallowly sunken throughout; pore-pairs uniserial and densely crowded adapically, the two columns being separated by a broad perradial zone of granules.
  • Other ambulacra petaloid and cruciform, ending well before the ambitus. Petals sunken and straight-sided; closed distally.
  • Posterior petals not confluent adapically.
  • Periproct towards the top of the near-vertical truncate face.
  • Peristome wider than long; kidney-shaped.
  • Labral plate short and wide, in broad contact with following sternal plates. Extending to the second ambulacral plate.
  • No large primary tubercles differentiated. Aboral tubercles and spines relatively fine and uniform.
  • Plastron wide and well-developed; formed of sternal and episternal plates.
  • Fully formed peripetalous and subanal fascioles. Peripetalous fasciole indented by one plate behind the anterior petals. Subanal fasciole bilobed.
Distribution
Eocene to Recent, Indo-Pacific, Atlantic, Mediterranean
Name gender neuter
Type
Brissopsis duciei Wright, 1855, p. 37, by original designation.
Species Included
Lambert & Thiery (1921, p. 488-9) included many species in this genus, including Brissopsis lyrifera, in the mistaken belief that the type of Brissopsis was B. elegans.
Classification and/or Status

Spatangoida, Micrasterina, Brissopsidae.

Subjective junior synonym of Brissopsis Agassiz, in Agassiz& Desor, 1847.

Remarks

Brissopsis duciei is very close to Brissopsis lyrifera and there is nothing of substance to distinguish Brissoma from Brissopsis.

Lambert, J. & Thiery, P. 1909-1925. Essai de Nomenclature raisonnee des Echinides. Chaumont; L. Ferriere.

Pomel, A. 1888. Paléontologie ou descriptions des animaux fossiles de l’Algérie: 2, Echinodermes (2 volumes). Publications du Service de la Carte géologique de l’Algérie, 344 pp., 120 pls.