''Olenina'' is an extinct suborder of the

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 ...

order Ptychopariida.

Subdivisions

*Superfamily Olenoidea **Family Ellipsocephaloididae **Family

Olenidae Olenidae is a family of ptychopariid trilobites. Some genera, ''Balnibarbi'' and ''Cloacaspis'', are thought to have evolved a symbiotic relationship with sulfur-eating bacteria from which they derived nutrition. Genera * Acerocare * Aceroca ...

*Superfamily ''Incertae sedis'' **Genus ''

Triarthrus ''Triarthrus'' is a genus of Upper Ordovician ptychopariid trilobite found in New York, Ohio, Kentucky, and Indiana, eastern and northern Canada, China and Scandinavia. It is the last of the Olenid trilobites, a group which flourished in the Camb ...

References

Ptychopariida Arthropod suborders {{ptychopariida-stub