Olenoides

Olenoides
Ogyopsis klotzi from the Mt. Stephen Trilobite Beds (Middle Cambrian) near Field, BC, Canada.
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Trilobita
Order: Corynexochida
Family: Dorypygidae
Genus: Olenoides

Olenoides was a trilobite from the Cambrian period. Its fossils are found well-preserved in the Burgess Shale in Canada. It grew up to 10 cm long.

Olenoides followed the basic structure of all trilobites — a cephalon (head shield), a thorax with seven jointed parts, and finally a semicircular pygidium. Its antennae were long, and curved back along its sides. Its thin legs show that it was no swimmer, instead crawling along the sea floor in search of prey. This is also evidenced by fossil tracks that have been found. Conspicuous W-shaped wounds, often partially healed, on Olenoides specimens may be due to predation by Anomalocaris.[1]

Its major characteristics are a large parallel-sided glabella, deep interpleural furrows on the pygidium, and slender pygidial spines, as well as the fact that it is the most common limb-bearing trilobite species in the Burgess Shale.

Specimens have been found in the Marjumian of the USA (Utah and New York). General Cambrian fossils have been found in Canada (British Columbia and Newfoundland), Greenland, Kazakhstan, Russia, and the USA (Idaho, Nevada for which O. nevadensis is named, New York, Pennsylvania for which O. pennsylvanicus is named, Virginia, Utah, and Wyoming).[2]

213 specimens of Olenoides are known from the Greater Phyllopod bed, where they comprise 0.4% of the community.[3] The Burgess Shale's preservative qualities have helped Olenoides become one of the best known of trilobites.

Contents

Synonyms

Olenoides was formerly known as Neolenus. Kootenia is sometimes considered a junior synonym because the main morphological difference between the two genera was Kootenia 's lack of Olenoides' strong interpleural furrows on the pygidium, which is now believed to be variable. [4]

Species

External links

References

  1. ^ Coppold, Murray and Wayne Powell (2006). A Geoscience Guide to the Burgess Shale, p.60. The Burgess Shale Geoscience Foundation, Field, British Columbia. ISBN 0978013204.
  2. ^ Paleobiology Database. [http://paleodb.org/cgi-bin/bridge.pl?a=basicTaxonInfo&taxon_no=20399 "Chancia", accessed March 27, 2011
  3. ^ Caron, J. -B.; Jackson, D. A. (October 2006). "Taphonomy of the Greater Phyllopod Bed community, Burgess Shale". PALAIOS 21 (5): 451–465. doi:10.2110/palo.2003.P05-070R.  edit
  4. ^ Coppold, Murray and Wayne Powell (2006). A Geoscience Guide to the Burgess Shale, p.59. The Burgess Shale Geoscience Foundation, Field, British Columbia. ISBN 0978013204.

Olenoides on the Smithsonian institution website

A fossil photograph of Olenoides nevadensis This trilobite fossil is about 50 mm. long. It was found in the Marjum Formation in Utah. [Note - 25.4 mm=1 inch.]