The Echinoid Directory

Fibularia Lamarck, 1816, p. 16

[=Fibulina Tornquist, 1904, p. 327, type species Fibulina gracilis Tournquist, 1904; =Tarphypygus H.L. Clark, 1927, type species T. ellipticus H. L. Clark, 1927 ]

Diagnostic Features
  • Small subglobular test with thick rounded margins; typically somewhat pointed anteriorly and posteriorly.
  • No internal buttressing of any sort.
  • Apical disc central with four gonopores. Hydropores few, sometimes in a groove.
  • Petals small but distinct, generally comprising just a few pore-pairs each.
  • Peristome small and sunken.
  • Periproct oral, close to peristome; opening bounded by first and second paired interambulacral plates.
  • Basicoronal circlet small, with interambulacral plates a little wider than ambulacral plates but not projecting.
  • Aborally interambulacral zones end in two successive plates in the type species.
Eocene to Recent, widely distributed.
Name gender feminine
Fibularia ovulum Lamarck, 1816, p. 17, by ICZN ruling (Op. 207, p. 350).

ICZN 1954. Opinion 207. Designation, under the Plenary Powers, of the type species in harmony with accustomed use for the genera Echinocyamus van Phelsum, 1774, and Fibularia Lamarck, 1816 (Class Echinoidea). Opinions and Declarations rendered by the International Commission on Zoological Nomenclature 3, 339-352.
Species Included

Mortensen (1948) records five extant species from the Indo-West Pacific. Fossil species are mostly poorly documented and include:

  • F. cribellum Meijere, 1904; Pleistocene-Recent, Japan-Philippines-Malaysia.
  • F. gregata Tate, 1885; late Middle Eocene to Early-Middle Miocene, Australia.
  • F. guvarensis Srivastava, 1978; early Miocene, India.
Classification and/or Status

Clypeasteroida; Scutellina; Laganiformes; Fibulariidae.



The absence of internal buttressing distinguishes this genus from Echinocyamus. Fibulariella differs in details of periproctal and peristomial plating, pedicellarial structure and tube-foot spiculation but is difficult to separate on test characters. Taphryphygus and Fibulina are very close but differ in having four or more single interambulacral elements adapically in each zone. However, they are also larger and this may simply be a reflection of size.

Lam,arck, J. P. B. M. 1816. Histoire naturelle des animaux sans vertèbres, présentant les caractères généraux et particuliers de ces animaux, leur distribution, leur classes, leurs familles, leurs genres, et le citation des principales espèces qui s'y rapportent; précédée d'une Introduction offrant la Détermination des caractères essentiells de l'animal, sa distinction du végétal et des autres corps naturels, enfin, l'Exposition des Principes fondamentaux de la Zoologie. tome 3, 770 pp. Verdière, Paris.

Mortensen, T. 1948. A Monograph of the Echinoidea IV.2 Clypeasteroida. C. A. Reitzel, Copenhagen.

Durham, J. W. 1955. Classification of clypeasteroid echinoids. University of California Publications in Geological Sciences 31, 73-192.