Nileidae is a family of

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 ...

s of the

Asaphida Asaphida is a large, morphologically diverse order of trilobites found in marine strata dated from the Middle Cambrian until their extinction during the Silurian. Asaphida contains six superfamilies (Anomocaroidea, Asaphoidea, Cyclopygoidea, Di ...

order. These fast-moving nektonic carnivores lived in the

Ordovician The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era, and the second of twelve periods of the Phanerozoic Eon (geology), Eon. The Ordovician spans 41.6 million years f ...

and

Cambrian The Cambrian ( ) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordov ...

periods.

Genera

*'' Aocaspis'' Dolambi and Gond 1992 *'' Barrandia'' McCoy 1849 *'' Borthaspidella'' Rasetti 1954 *'' Bumastides'' Veber 1948 *'' Homalopteon'' Salter 1867 *'' Illaenopsis'' Salter 1865 *'' Kodymaspis'' Prantl and Pribyl 1950 *'' Neopsilocephalina'' Yin 1978 *'' Nileus'' Dalman 1827 *'' Parabarrandia'' Prantl and Pribyl 1949 *'' Peraspis'' Whittington 1965 *'' Petrbokia'' Pribyl and Vanek 1965 *'' Platypeltoides'' Pribyl 1949 *'' Poronileus'' Fortey 1975 *'' Psilocephalinella'' Kobayashi 1951 *'' Symphysurina'' Ulrich 1924 *'' Symphysurus'' Goldfuss 1843 *'' Varvia'' Thernvik 1965

References

Cyclopygoidea Trilobite families Cambrian first appearances Ordovician extinctions {{Asaphida-stub