The Echinoid Directory

Gonimaretia H.L. Clark, 1917, p. 240

Diagnostic Features
  • Test ovate without anterior sulcus; depressed in profile with flat base and low arched upper surface.
  • Apical disc ethmolytic, with 3 gonopores; central.
  • Anterior ambulacrum narrow and flush; pore-pairs small, simple isopores. Other ambulacra petaloid and flush.
  • Anterior paired petals bowed with adapical pore-pairs in anterior column rudimentary; remainder large and conjugate; pore-pair columns of posterior petals converge distally.
  • Periproct on short vertical truncate face; only slightly sunken.
  • Peristome wider than long; kidney-shaped; far removed from the anterior.
  • Spaheridia set in deep pits in adoral ambulacral plates.
  • Labral plate narrow and elongate; only just contacting sternal plates; Extending to ambulacral plate 2.
  • Paired sternal plates narrow and triangular; fully tuberculate. Episternal plates narrowing posteriorly.
  • Aboral tuberculation mostly fine and uniform but with a small number of primary tubercules towards the ambitus in the lateral interambulacrum. Primary tubercles with sunken areoles. Oral tubercles prominent laterally and arranged in distinct rows.
  • Well-developed shield-shaped subanal fasciole.
Recent, Philippines, 235-2460 m.
Name gender feminine
Gonimaretia tylota Clark, 1917, p. 241, by original designation.
Species Included
  • G. tylota Clark, 1917; Recent, Philippines.
Classification and/or Status

Spatangoida, Micrasterina, Maretiidae.

Subjective junior synonym of Pseudomaretia Koehler, 1914 [=Nacospatangus A Agassiz, 1873].


Distinguished from Pseudomaretia by having a fully tuberculate sternum and by having the periproct flush on the posterior face rather than sunken. Mortensen (1950) chose to synonymize the two.

Clark, H. L. 1917. Hawaiian and other Pacific Echini. Memoirs of the Museum of Comparative Zoology, Harvard College, 46, 85-283.

Mortensen, T. 1950. A monograph of the Echinoidea. V.2. C. A. Reitzel, Copenhagen.