The Echinoid Directory

Contributed by Andrew Smith, January 2009

Jolyclypus Lambert, 1918, 26

Diagnostic Features
  • Test small (up to 11 mm), with low profile
  • Apical disc eccentric anteriorly, 4 genital plates of equal size organized into arc around anterior edge of periproct.  No supplementary plates in disc.  Sexual dimorphic, with large gonopores in females
  • periproct supramarginal, opening extending from apical disc and situated in a deep narrow mongitudinal groove.  Extending backards to midway between the apical system and posterior test margin
  • Peristome anterior; no phyllodes or occluded plates
Distribution Cenomanian, Upper Cretaceous, France
Name gender masculine
Type Galeropygus jolyi Gauthier, 1898, p. 837.

Neotype:  MNHN-DHT R65001, erected by Saudede & Neraudeau, 2006, p. 544.
Species Included Only the type species
Classification and/or Status Irregularia, Cassiduloida,

Subgenus of Nucleopygus Agassiz, 1840 according to Saucede & Neraudeau (2006)
Remarks See Saudede & Neraudeau (2006) for a complete description and discussion. Nicolleau & Vadet (2010) accept Jolyclypus at genus level.

Gauthier, V. 1898. Contribution a l\'etude des echinides fossiles. Bulletin de la Societe Geologique de France 25(3), 831-841.

Lambert, J. 1918. Considérations sur la classification des Échinides Atélostomes. I. Brachygnata et Procassiduloida . Mémoires de la Société Académique d'Agriculture des Sciences, Arts et Belles-Lettres du Département de l'Aube, Troisième Série 55((Vol. 82 of the whole series)): 9-54.

Saucede, T. & Neraudeau, D. 2006. An \'Elvis echinoid, Nucleopygus (Jolyclypus) jolyi, from the Cenomanian of France: phylogenetic analysis, sexual dimorphism and neotype designation. Cretaceous Research 27, 542-554.

Nicolleau, P. & Vadet, A. 2010. Etude sur le genre Jolyclypus: Nucleopygus ou Aulacopygus? Annales de la Societe d\'Histoire Naturelle du Boulonnais 9/2, 1-16.