Prehistoric animal orders

thumb|right|Trepostome bryozoan with bioerosion; [[Bellevue Formation, Upper Ordovician (Katian), northern Kentucky.]]

Bourgueticrinida is an order of crinoids that typically live deep in the ocean. Members of this order are attached to the seabed by a slender stalk and are known as sea lilies. While other groups of crinoids flourished during the Permian, bourgueticrinids along with other extant orders did not appear until the Triassic, following a mass extinction event in which nearly all crinoids died out.

Fenestrida is an extinct order of bryozoans in the class Stenolaemata.

Millericrinida is an order of articulate crinoids that originated in the Anisian (Middle Triassic).

Cystoporida, also known as Cystoporata or cystoporates, are an extinct order of Paleozoic bryozoans in the class Stenolaemata. Their fossils are found from Ordovician to Triassic strata.

The Scleronychophora or armoured lobopods are a group of lobopodians (such as the hallucigeniids and microdictyon) that bear a robust dorsal armature of paired plates.