A monospecific order of Asteroidea established for Trichasteropsis wiessmanni, the only Triassic asteroid known from articulated specimens. It is a small starfish with a relatively large disc and short arms. The skeleton is differentiated into marginals, actinals, and abactinals, the marginals comprising a single series of blocklike ossicles. The abactinal surface is composed of larger stellate plates and smaller rods and granules; a carinal row is present. Oral plates are large and well developed. Pedicellariae are not present. Trichasteropsis is the most primitive post-Paleozoic asteroid known and lies close to the latest common ancestor of all living asteroids. It comes from the Muschelkalk (Middle Triassic, Anisian-Ladinian) of Germany.