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

lichid Lichida is an order of typically spiny trilobite that lived from the Furongian to the Devonian period. These trilobites usually have 8–13 thoracic segments. Their exoskeletons often have a grainy texture or have wart or spine-like tubercles. S ...

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 ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

from the Early

Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, whe ...

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

New York State New York, officially the State of New York, is a state in the Northeastern United States. It is often called New York State to distinguish it from its largest city, New York City. With a total area of , New York is the 27th-largest U.S. stat ...

and

Ontario Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...

. 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 (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 ...

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

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 cre ...

consists of around 11 segments. The

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

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 In zoology, the hypostome can refer to structures in distinct animal groups: *Hypostome (trilobite), the ventral mouthpart plate in trilobites *Hypostome (tick) The hypostome (also called the maxilla, radula, or labium) is a calcified harpoo ...

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