The Echinoid Directory

Emiratia Ali, 1990, p. 103

Diagnostic Features
  • Test flattened below and weakly domed above.
  • Apical disc small, pentagonal, about one-quarter test diameter; plating monocyclic with large periproctal area, but plates usually lost.
  • Ambulacra straight, and moderately wide; plating polygeminate throughout; pore-pairs uniform and undifferentiated; biserially arranged at ambitus and above, with small primary tubercle to each compound plate; arcuate at ambitus and straight adorally; no phyllodes. Primary ambulacral tubercle to each plate; plate compounding diadematid, with all elements reaching the perradius and all overlapped by the primary tubercle at the ambitus.
  • Interambulacral plates wider than tall; with two subequal primary tubercles on ambital plates; the outer series reducing in size adapically and adorally. Narrow interradial zone of small secondaries and granules widening a little adapically.
  • A naked interradial zone is present adapically in the interambulacra.
  • Ambulacral and interambulacral tubercles similar in size; perforate and crenulate.
  • Peristome about one-third test diameter, rather deeply sunken; buccal notches small but clearly marked and with lip. No sphaeridial pits.
  • Spines and lantern unknown.
Distribution
Cretaceous (Albian-Cenomanian) Middle East and western Indian Ocean.
Name gender feminine
Type
Emiratia raskhaimahensis Ali, 1990, p. 103 by original designation.
Species Included
Only the type species.
Classification and/or Status

Euechinoidea, Calycina, Phymosomatoida, Emiratiidae, Emiratiinae.

Monotypic.

Remarks

This taxon combines the sunken peristome and lack of phyllodes of Allomma with the bigeminate ambulacra of Tetragramma. No other emiritiid has biserial pore zones adapically.

Ali, M. S. M. 1990. Cenomanian echinoids from Ras al Khaimah, United Arab Emirates. Neues Jahrbuch fur Mineralogie, Geologie und Palaontologie, Abhandlungen, 179, 97-116.