The Echinoid Directory

Cordastrum Nisiyama, 1968, p. 175

Diagnostic Features
  • Test cordate with posterior face projecting as strong heel. Test inflated in profile.
  • Apical disc ethmophract with ?four gonopores; anterior.
  • Ambulacrum III in deep groove; pore-pairs small and rounded.
  • Paired ambulacra slightly depressed and subpetaloid aborally; anterior petals about twice length of posterior petals.
  • Peristome small and circular; positioned towards the anterior border and facing obliquely forward into frontal groove.
  • Plastron plating elongate. Labral plate long and narrow; extending to ambulacral plate 3. Sternal plates narrow, elongate and symmetric; only slightly longer than labral plate. Episternal plates small and biserially offset.
  • Periproct on posterior inclined face; visible in aboral view.
  • Peripetalous fasciole present; steeply inclined and dipping below the ambitus around the anterior.
  • Aboral tuberculation fine and set in a dense granulation.
Distribution
Upper Cretaceous, Japan.
Name gender neuter
Type
Cottreaucorys (Cordastrum) sulcatus Nisiyama 1968, p. 175, by original designation. Holotype IGPS 73746.
Species Included
  • Only the type species.
Classification and/or Status

Spatangoida, Hemiasterina, Aeropsidae.

Monotypic.

Remarks

Differs from Cottreaucorys in having a broad and deep frontal groove and better developed petals.

Nisiyama, S. 1968. The echinoid fauna from Japan and adjacent regions part II. Palaeontological Society of Japan Special Papers 13, 1-491, pls 1-30.