Crinoidea, gen. indet.

Crinoids are echinoderms — relatives of starfish and sea urchins — which lived anchored to the sea floor on a flexible stalk, filtering food from the current with a crown of feathery arms. They look like plants and are commonly called sea lilies, but they are animals.

The skeleton is built of many separate calcite plates held together by ligament. When the animal died those plates came apart within days, so crinoids are almost always found as scattered stem discs rather than whole individuals. Beds of Palaeozoic limestone are made largely of this debris.

Crinoids were devastated by the end-Permian extinction but did not die out; several hundred species live in the oceans today.