The Echinoid Directory

Brissus Gray, 1825, p. 431

[=Bryssus Martens, 1869, p. 128 (objective homonym); = Allobrissus Mortensen, 1950, type species Brissus agassizi Doderlein, 1855, p. 36; = Sandiegoaster Sanchez Roig, 1952, p. 12, type species S. durhami Sanchez Roig, 1952, p. 12. ]

Diagnostic Features	Test ovate without anterior sulcus; rounded in profile. Apical disc ethmolytic, with 4 gonopores. Madreporic plate projecting well posterior of the other apical disc plates; anterior of centre. Anterior ambulacrum narrow and flush; pore-pairs small, simple isopores (no penicillate tube-feet). Other ambulacra petaloid and depressed, the anterior pair almost at 180 degrees. Petals sunken and straight-sided; closed distally. Perradial zone between columns of pore-pairs very narrow. Periproct large; on short vertical truncate face; oral side framed by interambulacral plates 5a5/5b5. Peristome wider than long; kidney-shaped; oblique so as to face forwards. Labral plate short and wide, in broad contact with following sternal plates. No large primary tubercles differentiated. Aboral spines coarser around anterior half of test aborally. Plastron very broad and distinctly bowed laterally. Well-developed peripetalous and subanal fascioles. Subanal fasciole bilobed; usually enclosing 4 penicillate tube-feet on each side. Passing over middle of interambulacral plates 3 on oral side and across plates 4-6 on aboral side. Peripetalous fasciole indented in all five interambulacra.
Distribution	Eocene to Recent; tropical to mid-latitude countries and Indo-Pacific, Atlantic, Mediterranean. Mostly shallow water sands to shell gravels - infaunal.
Name gender	masculine
Type	Spatangus brissus unicolor Leske, 1778, p. 248, by ICZN ruling, 1948.
Species Included	Many named species, including: B. unicolor (Leske, 1778); Upper Miocene to Recent, Atlantic and Mediterranean B. latecarinatus (Leske, 1778); Miocene to Recent, Indo-Pacific B. gigas Fell, 1947; Recent, New Zealand B. obesus Verrill, 1867; Recent West coast of central America B. agassizii Doderlein, 1885; Recent, Japan B. meridionalis Mortensen, 1950, Recent, Australia and Norfolk Island B. fosteri McNamara, Philip & Kruse, 1986; Early Miocene (Longfordian), South Australia B. glenni Cooke, 1959; Late Miocene, South Carolina, USA B. latidunensis Clegg, 1933; Lower Miocene (Burdigalian), Iran and Saudi Arabia B. agassizi Doderlein [includes B. gigas Fell, 1947]; Recent, southern Australia, New Zealand to Japan B. cabererai (Sanchez Roig, 1953); Late Eocene, Cuba B. camagueyensis Weisbord, 1934; Late Eocene, Cuba B. caobaense Sanchez Roig, 1953; Middle or Late Eocene, Cuba B. durhami (Sanchez Roig, 1952); Middle or Late Eocene, Cuba B. minutus (Sanchez Roig, 1949); Oligo-Miocene, Cuba. B. aequipetala Gregory, 1891; Miocene, Malta B. lasti Stockley, 1928; Pliocene, Zanzibar. B. oblongus Wright, 1855; Miocene, Malta. B. depressus Gregory, 1891; Miocene, Malta
Classification and/or Status	Spatangoida, Micrasterina, Brissidae. Presumed paraphyletic, by exclusion of Anabrissus and others.
Remarks	Distinguished from Anabrissus only by having well developed petals. Similar to Brissomorpha, but that genus has flush petals with a relatively wide perradial zone between columns of pore-pairs. It also has a lateroanal fasciole. Gray, J. E. 1825. An attempt to divide the Echinida, or sea eggs, into natural families. Annals of Philosophy, new series, 10, 423-431. Mortensen, T. 1951. A monograph of the Echinoidea. V. Spatangoida 2. C. A. Reitzel, Copenhagen.