Montecaris possesses an unornamented, bivalved carapace which terminates in a spiny posterior. Its caudal tail fin is trifurcated and dagger-like. Species of Montecaris from Europe and Canada are no more than 15 cm (5.9 in) in length, while M. gogoensis from the Gogo Formation of Australia can reach lengths of 24 cm (9.4 in) and, rarely, up to 60 cm (2.0 ft).[6][7]
Due to its streamlined carapace and large tail fin, Montecaris was likely an active nektonic swimmer, which primarily appears in deep water sediments. Its robust mandibles and powerful musculature suggests a carnivorous lifestyle as an active predator or scavenger.[7]
^ abJux, U. (1960). "Montecaris lehmanni, a new crustacean from the Rhenish Devonian and the problem of its systematic position". Journal of Paleontology (34): 1129–1152 – via JSTOR.
^ abcChlupač, I. (1960). "Die Gattung Montecaris Jux (Crustacea, Phyllocarida) im alteren Paläozoikum der Tschechoslowakei". Geologie (9): 638–649.
^ abV.N., Krestovnikov (1961). "Novyye rakoobraznye fillokaridy Paleozoya Russkoi platformy, Urala, Timana i Donbassa [New phyllocarid crustaceans from Palaeozoic of the Russian plateau, the Urals, Timan and the Donetz Basin]". Trudy Geologicheskogo Instituta (52): 1–67.