The Echinoid Directory

Hemimaretia Mortensen, 1950, p. 160

Diagnostic Features
  • Test fragile; ovate with shallow but distinct anterior sulcus; posterior face truncate. Test depressed in profile.
  • Apical disc ethmophract with three gonopores (no gonopore on G2); closer to anterior than centre.
  • Amb III flush aborally, narrow, with simple plates and rudimentary tube-feet.
  • Petals short and flush with small non-conjugate pore-pairs. Only the distal pore-pairs developed in the anterior column of the anterior paired petals.
  • Peristome D-shaped; downward facing. Phyllodes very poorly developed.
  • Plastron plating: labral plate very long and narrow; wedge-shaped; extending to rear of second amb. plate which is enlarged. Sternal plates small and triangular, lacking tubercles adorally. Episternal plates paired and narrowing posteriorly; indented by amb plate 6.
  • Periproct on posterior truncate face.
  • Subanal fasciole present; shield-shaped, enclosing two funnel building tube-feet on each side.
  • Primary aboral tuberculation mostly rather uniform, with primary tubercles towards ambitus in lateral Iamb zones - these tubercles sunken and forming internal ampullae.
  • Latero-oral tubercles with spiralled parapet.
Recent, East Africa 693 m.
Name gender feminine
Maretia elevata Doderlein, 1906, p. 263, by original designation.
Species Included
  • Only the type species.
Classification and/or Status

Spatangoida, Micrasterina, Maretiidae.



Differs from Lovenia in lacking an inner fasciole. Close to Nacospatangus.


Mortensen, T. 1951. A monograph of the Echinoidea. V. Spatangoida 2. C. A. Reitzel, Copenhagen.