The Echinoid Directory

Contributed by Andrew Smith, October 2006

Ekerekeia Ozdikmen & Udoh, 2010, p. 340

[=Farquharsonia Currie, 1927, p. 416, non Farquharsonia Collin, 1922 (Insecta: Diptera)]

Diagnostic Features
  • Test medium sized; low hemispherical in profile.
  • Apical disc small, plating hemicyclic with ocular plates V and I insert. Rim of periproct smooth and subcircular; plates covered in fine granulation.
  • Ambulacra straight with wide perradial zone. Pore-pairs arranged uniserially throughout. Plating of simple triads with all three elements reaching the perradial suture; two elements overlain by a small primary tubercle placed close to the pore-pairs, the third element with granules only. Perradial zone broad and covered in dense uniform granules.
  • Interambulacral plates wider than tall, bearing a single, subcentral primary tubercle. Tubercles much smaller towards the apex, largest at the ambitus and continuing to the peristome. Adradial and interradial bands of fine granules well developed on all plates and more prominant aborally.
  • All tubercles perforate and mostly crenulate (but with some non-crenulate tubercles adapically).
  • Peristome about 1/3 of test diameter, slightly sunken and with sharp and relatively deep buccal notches. Smooth adradial zone immediately behind the buccal notches but no raised tag.
  • Spines and lantern unknown
Distribution Middle Jurassic (Bathonian-Callovian) of Saudi Arabia and Somalia
Name gender feminine
Type Farquharsonia somaliensis Currie, 1927, p. 416, by original designation.
Species Included
  • E. somaliensis (Currie, 1927); Bathonian - Callovian, Somalia, Saudi Arabia.
  • E. crenulata (Kier, 1972); Bathonian, Saudi Arabia
Classification and/or Status Acroechinoidea, Diadematoida, Heterodiadematidae
Remarks The type species, along with a second species, were described in admirable detail by Kier (1972).  The original name Farquharsonia proposed by Currie is preoccupied, and this is a replacement name (see Ozdikmen & Udoh 2010).

Özdikmen, H.  & Udoh, A. U. 2010. Ekerekeia nom. nov., a Replacement Name for Farquharsonia Currie, 1928 (Echinodermata: Euechinoidea), Preoccupied by Farquharsonia Collin, 1922 (Insecta: Diptera). African Zoology, 45, 340-341 [doi: 10.3377/004.045.0213]

Currie, E. D. 1927. Jurassic and Eocene Echinoidea from Somaliland. Transactions of the Royal Society of Edinburgh 55, 411-441, 1 pl.

Kier, P. M. 1972. Tertiary and Mesozoic echinoids of Saudi Arabia. Smithsonian Contributions to Paleobiology 10, 1-242.