''Levisoceras'' is a genus of early Ordovician

ellesmerocerid The Ellesmerocerida is an order of primitive cephalopods belonging to the subclass Nautiloidea with a widespread distribution that lived during the Late Cambrian and Ordovician. Morphology The Ellesmerocerida are characterized by shells that ar ...

cephalopod A cephalopod is any member of the molluscan class Cephalopoda (Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head ...

s.Flower, R.H. 1964. The Nasutiloid Order Ellesmerocerida (Cephalopoda); Memoir 12, New Mexico Bureau of Mines and Mineral Resources, Socorro N.M.

Morphology

''Levisoceras'' is a distinctive ellesmeroceratid that combines rapid expansion a strong endogastric curvature. The cross section is compressed with the height increasing more rapidly than the width. The siphuncle is ventral and expands much as the shell itself. In one specimen the height was found to be around four centimetres and the width 2.5 cm. The septa are approximately flat.

Taxonomic Relations

Some 14 or so species have been named. Those more gently expanding approach '' Dakeoceras'' in form. There is also an apparent transition between ''Levisoceras'' and '' Burenoceras''.

Ecology

''Levisoceras'' was carnivorous and lived on, and swum above, the sea floor.

References

Prehistoric nautiloid genera Ordovician cephalopods Ordovician cephalopods of North America Ellesmerocerida {{paleo-Nautiloidea-stub