''Thaleops'' is an extinct genus of

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 At ...

of the family

Illaenidae The Illaenidae are a family of trilobites in the order Corynexochida. 223 currently accepted species in 24 genera are known from the Ordovician. Some scholars include the Panderiidae in the Illaenidae, but this is not generally supported. Distr ...

. It lived from the

Floian The Floian is the second stage of the Ordovician Period. It succeeds the Tremadocian with which it forms the Lower Ordovician epoch. It precedes the Dapingian Stage of the Middle Ordovician. The Floian extended from to million years ago. The lowe ...

to the

Katian The Katian is the second stage of the Upper Ordovician. It is preceded by the Sandbian and succeeded by the Hirnantian Stage. The Katian began million years ago and lasted for about 7.8 million years until the beginning of the Hirnantian million ...

of the

Ordovician The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period million years ago (Mya) to the start ...

in what is now

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

. ''Thaleops'' can be told apart from other illaenids because of the cheek spines that many

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

possess under their eyes. ''Thaleops'' had a large distribution range, With some species being found in parts of

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

to some U.S states including

Oklahoma Oklahoma (; Choctaw language, Choctaw: ; chr, ᎣᎧᎳᎰᎹ, ''Okalahoma'' ) is a U.S. state, state in the South Central United States, South Central region of the United States, bordered by Texas on the south and west, Kansas on the nor ...

Wisconsin Wisconsin () is a state in the upper Midwestern United States. Wisconsin is the 25th-largest state by total area and the 20th-most populous. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake M ...

, 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 * '' ...

. It is thought to have lived in shallow water, as a study published in Oklahoma found that

deposits A deposit account is a bank account maintained by a financial institution in which a customer can deposit and withdraw money. Deposit accounts can be savings accounts, Transaction account#Current accounts, current accounts or any of several othe ...

that contained ''Thaleops'' and the asaphid trilobite '' Bumastides'' contained 4 times as many trilobite genera, where associated with shallow water areas.

Classification

Classification of ''Thaleops'', ''

Illaenus ''Illaenus'' is a genus of trilobites from Russia and Morocco, from the middle Ordovician The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.6 million years from the end ...

'', and '' Nanillaenus'' by Amati & Westrop, 2004. ''Thaleops''

References

{{Taxonbar, from=Q109975590 Trilobite genera Trilobites of North America Ordovician trilobites Illaenina