''Olenoides'' was a

trilobite Trilobites (; meaning "three lobes") are extinct marine arthropods that form the class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the ...

from the

Cambrian The Cambrian Period ( ; sometimes symbolized Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ag ...

period. Its fossils are found well-preserved in the

Burgess Shale The Burgess Shale is a fossil-bearing deposit exposed in the Canadian Rockies of British Columbia, Canada. It is famous for the exceptional preservation of the soft parts of its fossils. At old (middle Cambrian), it is one of the earliest fos ...

in Canada. It grew up to 10 cm (3.9 in) long.

Etymology

''Olenoides'' – from ''Olenus'', in Greek mythology a man who, along with his wife Lethaea, was turned to stone. ''Olenus'' was used for a trilobite genus name in 1827; the suffix -''oides''(“resembling”) was added later.

Discussion

''Olenoides'' followed the basic structure of all trilobites — a cephalon (head shield), a

thorax The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the crea ...

with seven jointed parts, and finally a semicircular

pygidium The pygidium (plural pygidia) is the posterior body part or shield of crustaceans and some other arthropods, such as insects and the extinct trilobites. In groups other than insects, it contains the anus and, in females, the ovipositor. It is compo ...

. 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 ''Anomalocaris'' ("unlike other shrimp", or "abnormal shrimp") is an extinct genus of radiodont, an order of early-diverging stem-group arthropods. The first fossils of ''Anomalocaris'' were discovered in the ''Ogygopsis'' Shale of the Stephen ...

''. Its major characteristics are a large parallel-sided

glabella The glabella, in humans, is the area of skin between the eyebrows and above the nose. The term also refers to the underlying bone that is slightly depressed, and joins the two brow ridges. It is a cephalometric landmark that is just superior ...

, deep interpleural furrows on the

, and slender pygidial spines, as well as the fact that it is the most common limb-bearing trilobite species in the

. Specimens have been found in the

Marjumian The Cambrian Period ( ; sometimes symbolized Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ago ( ...

of the United States (

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its ...

and

New York New York most commonly refers to: * New York City, the most populous city in the United States, located in the state of New York * New York (state), a state in the northeastern United States New York may also refer to: Film and television * ...

). General

fossils have been found in Canada (

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, for ...

and

Newfoundland Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region ...

Greenland Greenland ( kl, Kalaallit Nunaat, ; da, Grønland, ) is an island country in North America that is part of the Kingdom of Denmark. It is located between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago. Greenland is ...

Kazakhstan Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbek ...

, Russia, and the USA (

Idaho Idaho ( ) is a state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Montana and Wyomi ...

Nevada Nevada ( ; ) is a state in the Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the 7th-most extensive, ...

for which ''O. nevadensis'' is named,

Pennsylvania Pennsylvania (; (Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, ...

for which O. pennsylvanicus is named,

Virginia Virginia, officially the Commonwealth of Virginia, is a state in the Mid-Atlantic and Southeastern regions of the United States, between the Atlantic Coast and the Appalachian Mountains. The geography and climate of the Commonwealth are ...

, and Wyoming). 213 specimens of ''Olenoides'' are known from the Greater

Phyllopod bed The Phyllopod bed, designated by USNM locality number 35k, is the most famous fossil-bearing member of the Burgess Shale fossil ''Lagerstätte''. It was quarried by Charles Walcott from 1911–1917 (and later named Walcott Quarry), and was t ...

, where they comprise 0.4% of the community. The Burgess Shale's preservative qualities have helped ''Olenoides'' become one of the best known of trilobites.

Synonyms

Olenoides serratus oblique with antennas

''Olenoides'' was formerly known as ''Neolenus''. Species of ''

Kootenia ''Kootenia'' is a genus of trilobites of the family Dorypygidae. 118 specimens of ''Kootenia'' are known from the Greater Phyllopod bed, where they comprise 0.22% of the community. Its major characteristics are that of the closely related '' Ol ...

'' are no longer considered different enough from those in ''Olenoides'' to warrant placement in a separate genus.Coppold, Murray and Wayne Powell (2006). ''A Geoscience Guide to the Burgess Shale'', p.59. The Burgess Shale Geoscience Foundation, Field, British Columbia. .

Species

* ''O. nevadensis'' * ''O. sassikaspa'' * ''O. serratus'' * ''O. dawsoni'' (formerly placed in ''Kootenia'') * ''O. burgessensis'' (formerly placed in ''Kootenia'') * ''O. buttsi'' (unrecognized) * ''O. convexus'' (unrecognized) * ''O. incertus'' (unrecognized) * ''O. pennsylvanicus'' (unrecognized)

Description

''Olenoides'' is an average size trilobite (up to 9 cm long), broadly oval in outline. Its cephalon is semi-circular. The glabella is parallel-sided, rounded at its front and almost reaches the anterior border. Narrow occular ridges curve backwards from the front of the glabella to the small, outwardly-bowed eyes. The librigenae narrow backward into straight, slender genal spines that reach as far as the third thorax segment. Thorax consists of seven segments that end in needle-like spines.

) has six axial rings that decrease in size backwards and four or five pairs of rearward pointing marginal spines. Cephalon, thorax and pygidium are of approximately equal length. ''Olenoides serratus'' is one of about twenty species of which the non-calcified parts are known, due to so-called soft tissue preservation. The antennae are the most anterior pair of appendages in trilobites. In ''O. serratus'', these are attached about halfway the immediately adjacent to the hypostome, and appear from the dorsal side under the cephalon in front of the side of the glabella. They were flexible, having a tubular shape that became narrower towards anterior and composed of between 40 and 50 segments that are each shorter than wide. ''Olenellus serratus'' is the only known trilobite with cerci,

uniramous The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments (called podomeres) are of Latin origin, and may be confused with terms for bones: ''coxa'' (meaning hip, plu ...

appendages on

ventral Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

side of last pygidial segment, and these are shaped like the antennas.

In Media

The Oleonoides genus is represented in the

Yu-Gi-Oh! is a Japanese manga series written and illustrated by Kazuki Takahashi. It was serialized in Shueisha's ''Weekly Shōnen Jump'' magazine between September 1996 and March 2004. The plot follows the story of a boy named Yugi Mutou, wh ...

card Paleozoic Olenoides.

References

''Olenoides'' on the Smithsonian institution website

''Paleozoic Olenoides Yu-Gi-Oh!''

External links

* This trilobite fossil is about 50 mm. long. It was found in the Marjum Formation in Utah. ote - 25.4 mm=1 inch. {{Taxonbar, from=Q2321982 Corynexochida genera Dorypygidae Burgess Shale fossils Fossil taxa described in 1877 Wheeler Shale Paleozoic life of Newfoundland and Labrador Cambrian trilobites Cambrian genus extinctions