Plectolites

Plectolites
Scientific classification
Class: Cephalopoda
Subclass: Nautiloidea
Order: Tarphycerida
Family: Trocholitidae
Genus: Plectolites
Flower, 1968

Plectolites is a coiled nautiloid cephalopod from Nevada (USA) somewhat reminiscent of the genus Plectoceras of the Barrandeocerina.

Plectolites is included in the Trocholitidae. The shell is strongly costate. Costae (ribs) slope back from the umbilical shoulder to the venter where they become sharply elevated. Whorls are slightly eccentric, the siphuncle dorsal of the center with thick connecting rings characteristic of the order. Plectolites has a ventral siphuncle with thin connecting rings.

The type species, Plectolites costatus Flower, comes form the sponge beds of the Pogonip Formation in Ikes Canyon, Toquima Range, Nev. The holotype is at Columbia University in New York city. Paratypes are at the U.S. National Museum in Washington D.C. and the New Mexico Museum and Natural History and Science in Albuquerque, New Mexico.

References

This article is issued from Wikipedia - version of the Monday, September 14, 2015. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.