†Ophiotrigonum Hess 1960 (brittle star)
Full reference: H. Hess. 1960. Ophiurenreste aus dem Malm des Schweizer Juras und des Departements Haut-Rhin. Eclogae geologicae Helvetiae 35(1):385-421
Parent taxon: Ophiuroidea according to W. K. Spencer and C.W. Wright 1966
Sister taxa: Ataxaster, Calclyra, Calclyridae, Calyptactis, Cheiropterasteridae, Encrinasteridae, Eophiuridae, Euryalida, Euzonosomatidae, Hallasteridae, Klasmuridae, Lumectaster, Myophiuroida, Oegophiurida, Oegophiuridea, Oegophiuroida, Ophiaulaxoides, Ophioflabellum, Ophioma, Ophiurella, Ophiurida, Ophiuridea, Phrynophiurida, Stenasteridae, Stenurida
Subtaxa: Ophiotrigonum oxfordiense
Type: Ophiotrigonum oxfordiense
Ecology: slow-moving low-level epifaunal detritivore-suspension feeder