Oligopygus Haldemani

Oligopygus was an Eocene sea urchin has a medium-sized test and is found throughout the south-eastern part of North America, the Caribbean, the West Indies, and Central America.

Identifiable featuresEdit

  • Test of medium size, elongate to subcircular in outline; margin and adoral surface rounded, sunken towards peristome
  • Apical system subcentral, monobasal, with four gonopores. Sexual dimorphism in size of genital pores (larger in females)
  • Petals well developed, open distally, anterior petal III longest, posterior pair (V & I) shortest. Pores strongly conjugate, equal number of pores in pores series in the same petal. Ambulacra beyond petals composed of primary plates, demiplates, and in some species included plates; demiplates and included plates small, thin, not reaching interior of test, absent near peristome
  • Peristome subcentral, opening subpentagonal to subtrigonal, in deep transverse depression or trough
  • Periproct inframarginal, midway between peristome and posterior margin
  • Buccal pores present on edge of peristome
  • Tubercles small, irregularly arranged both adorally and adapically

Species and locationsEdit

  • O. costuliformis Jeannet, 1928; Late Eocene, Trinidad
  • O. curasavica Molengraaff, 1929; Upper Eocene, Curacao
  • O. haldemani (Conrad, 1850); Late Eocene, Florida
  • O. jamaicensis Arnold & Clark, 1927; Middle Eocene, Jamaica

Oligopygus Sea Urchin

  • O. kugleri Jeannet, 1928; Late Eocene, Trinidad
  • O. nancei Cooke, 1941; Late Eocene, Venezuela
  • O. phelani Kier, 1967; Late Eocene, Florida, USA
  • O. pinguis Palmer in Sanchez Roig, 1949: Middle-Late Eocene, Cuba
  • O. putnami Israelsky; 1933; Upper Eocene, Mexico
  • O. rotundus Cooke, 1942; Late Eocene, Alabama, USA
  • O. sanchezi Lambert, 1932; Middle Eocene, Cuba
  • O. wetherbyi de Loriol, 1888; Late Eocene, Florida, USA
  • O. zyndeli Jeannet, 1928; Late Eocene, Trinidad


The Natural History Museum