†Euzonosoma montanum Raymond 1912 (brittle star)
Alternative combination: Schoenaster montanus
Full reference: P. E. Raymond. 1912. On two new Paleozoic starfish (one of them found near Ottawa), and a new crinoid [Palaester? wilsoni, Ordovician near Ottawa, Ontario, Mariacrinus? insuetus, Devonian, Three Forks Shale, Logan, Montana and Schaenaster montananus, Madison Limestone at Spring Canyon, near Alder, Mont.]. Ottawa Naturalist 26:77-81
Belongs to Euzonosoma according to W. K. Spencer 1930
Sister taxa: Euzonosoma goldfussi, Euzonosoma orbitoides, Euzonosoma pusillum, Euzonosoma schmidti
Type specimen: at the Carnegie Museum, Pittsburgh, Pennsylvania
Ecology: slow-moving low-level epifaunal detritivore-suspension feeder