Paradakeoceras

Paradakeoceras
Temporal range: Tremadocian
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Order: †Ellesmerocerida
Family: †Ellesmeroceratidae
Genus: †Paradakeoceras
Flower, 1964
Species
  • P. minor Flower, 1964
  • P. planiventrum Flower, 1964
  • Levisoceras complanatum Unklesbay, 1954 (Synonymous)
  • Burenoceras barnesi (Some specimens synonymous)

Paradakeoceras is an early Ordovician cephalopod belonging to the nautiloid order Ellesmerocerida.[1]

Morphology

The shell of Paradakeoceras is an expanding endogastric cyrtocone[1] with the siphuncle situated near the shell's concave margin.[2] A raised ring exists at the base of the body chamber, which is often preserved as a mould.[2]

Paradakeoceras was named by Flower, 1964,[1] for species previously included in Dakeoceras in which the cross section is broadened with consequent loss of lateral lobes in the suture.

Paradakeoceras shows a flattening of the venter which distinguishes it from Quebecoceras and has a reduction in the rate of expansion similar to that of Dakeoceras.

References

  1. 1 2 3 Flower, R. H. (1964). "The Nautiloid Order Ellesmerocerida". New Mexico Bureau of Mines and Mineral Resources. Memoir 12.
  2. 1 2 Kröger, B. R. (2007). "Some Lesser Known Features of the Ancient Cephalopod Order Ellesmerocerida (Nautiloidea, Cephalopoda)". Palaeontology 50 (3): 565–572. doi:10.1111/j.1475-4983.2007.00644.x.
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