The Echinoid Directory

Tripneustes L. Agassiz, 1841, p. 7

[ =Hipponoe Gray, 1840, p. 65 (nomen nudum), non Hipponoe Audouin & Milne Edwards, 1830; =Heliechinus Girard, 1850, type species Heliechinus Gouldii Girard, 1850 by monotypy (= Echinus ventricosus Lamarck) (subjective).]

Diagnostic Features
  • Apical disc hemicyclic, without suranal plate in adults.
  • Ambulacral plating trigeminate, with pore-pairs in three distinct columns throughout, these columns being separated by bands of tubercles (juveniles have simple arcs of pore-pairs).
  • Primary tubercle on every third or fourth ambulacral plate only.
  • Interambulacra with small primary tubercle on most but not all plates; secondary tubercles sparse and not regularly developed; plates appear rather naked.
  • Adapical interradial and perradial zones devoid of tubercles.
  • Buccal notches sharp and pronounced.
  • Auricles joined perradially.
Miocene to Recent, Caribbean, West coast of America, including Galapagos Islands, Southern Europe, Mediterranean and North Africa, and throughout the Indo-Pacific.
Name gender feminine
Tripneustes ventricosus (Lamarck, 1816) by monotypy.
Species Included
  • T. ventricosus (Lamarck, 1816); Recent, Caribbean and Atlantic - littoral to 30 m.
  • T. depressus A. Agassiz, 1863; Recent, Gulf of California, West Coast of Mexico, Galapagos Islands and Clarion Island.
  • T. gratilla (Linneus, 1758); Recent; Indo-Pacific- littoral to 75 m (with subspecies - see Dafni 1983). [Tripneustes fuscus Michelin, 1865 is a junior synonym]
  • T. antiquus Duncan & Sladen, 1855; Miocene of Pakistan.
  • T. proavia Duncan & Sladen, 1855; Miocene of Pakistan.
  • T. parkinsoni L. Agassiz, Miocene of southern France.
  • T. gahardensis (Seunes); middle and late Miocene of France and Spain.
  • T. Schneideri Boehm, Miocene **
  • T. tobleri Jeannet, 1928; Miocene of Venezuela.
  • T. californicus Kew, 1920; Pliocene of California.
Classification and/or Status

Camarodonta; Echinoida; Toxopneustidae.



The ambulacral structure, combined with the rather deep and sharp buccal notches make this readily identifiable in the fossil record. Only Toxopneustes has similar vertical pore-pair series and deep buccal notches, but in that species there are multiple subequal tubercles on interambulacral plates. Lytechinus tests are rather similar in tuberculation style but have a very different ambulacral pore-pair arrangement.

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

Dafni, J. (1983) A new sub-species of Tripneustes gratilla (L.) from the northern Red Sea (Echinodermata: Echinoidea: Toxopneustidae).Israeli Journal of Zoology 32:1-12.