''Terataspis'' is a comparatively huge, 60 centimetre long lichid

trilobite Trilobites (; meaning "three-lobed entities") are extinction, extinct marine arthropods that form the class (biology), class Trilobita. One of the earliest groups of arthropods to appear in the fossil record, trilobites were among the most succ ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

from the Early

Devonian The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian per ...

, about 397 million years ago. It lived in a shallow sea in what is now

New York State New York, also called New York State, is a state in the northeastern United States. Bordered by New England to the east, Canada to the north, and Pennsylvania and New Jersey to the south, its territory extends into both the Atlantic Ocean and ...

and

Ontario Ontario is the southernmost Provinces and territories of Canada, province of Canada. Located in Central Canada, Ontario is the Population of Canada by province and territory, country's most populous province. As of the 2021 Canadian census, it ...

. No whole specimens have been found, only disarticulated fragments of its exoskeleton, but enough fragments have been found to allow researchers to form reconstructions of the whole animal. The genus only contains one species, ''T. grandis''. ''Terataspis grandis'', like many other trilobites, was presumed to have been a

detritivore Detritivores (also known as detrivores, detritophages, detritus feeders or detritus eaters) are heterotrophs that obtain nutrients by consuming detritus (decomposing plant and animal parts as well as feces). There are many kinds of invertebrates, ...

that was also an opportunistic predator, preying on small burrowing animals, such as molluscs, worms, or arthropods.

Description

Almost the entire body of ''T.grandis'' is covered with spines and tubercles of varying sizes. The

pygidium The pygidium (: 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 compos ...

is large and shield-like with four pairs of slightly curved barbed spines on the sides. The

thorax The thorax (: thoraces or thoraxes) or chest is a part of the anatomy of 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 di ...

consists of around 11 segments. The

cephalon Cephalon, Inc. was an American biopharmaceutical company co-founded in 1987 by pharmacologist Frank Baldino Jr., Frank Baldino, Jr., neuroscientist Michael Lewis, and organic chemist James C. Kauer—all three former scientists with the DuPont ...

is characterized by its swollen front portion and longitudinal furrows that delineates a pair of swellings that located in line with the eyes. The hypostome is almost flat and kidney-shaped and has a poorly defined central body.Fossils of Ontario: Part 1: The Trilobites. Rolf Ludvigsen. 1979

References

{{Taxonbar, from=Q7701611 Lichida Devonian trilobites of North America Paleozoic life of Yukon