The Echinoid Directory

• Test medium-sized; inflated in profile with rounded ambitus; flattened above and below.
• Apical disc dicyclic, with gonopores close to the outer margin; inner region of genital plates tuberculate, forming a semi-regular ring around the periproct. Perirproct subcircular; periproct plates small and undifferentiated.
• Ambulacral plating trigeminate. Pore-pairs arranged with the middle pore-pair (on the occluded plate) adradial to the other two; forming a single adradial band. Not expanded adorally and no pore-crowding close to the peristome.
• Two subequal tubercles on each ambulacral plate.
• Wide perradial and interradial naked zones developed from apex to well beneath the ambitus.
• Small angular pits at sutural triple points on perradius and interradius; horizontal sutures without pits.
• Interambulacral plates with tuberculation confined to adradial margin from ambitus aborally. Central primary tubercle small and flanked by subequal tubercles latterally and above.
• Primary tubercles imperforate and non-crenulate.
• Peristomial with almost no buccal notches.
• Lantern camarodont.
• Spines small and simple.
• Globiferous pedicellariae with broad blade.

Recent; Indo-West Pacific.

Echinus globulus Linnaeus, 1758, p. 664, by original designation.

Only the type.

 Euechinoidea; Camarodonta; Temnopleuroida; Temnopleuridae.

Monotypic.

Distinguished by its broad naked perradial and interradial zones from most other temnopleurids. Distinguished from  Microcyphus by having interambulacral plates that are much wider than tall.

Mortensen, T. 1943. A monograph of the Echinoidea Part III.2, Camarodonta 1. C. A. Reitzel, Copenhagen.