Manania gwilliami is a species of stalked jellyfish found in intertidal and subtidal zones on the west coast of North America.[1] The stalk (peduncle) is described as being as long or longer than the calyx; the calyx typically has mottled pigmentation throughout. The name "gwilliami" refers to G.F. Gwilliam who described a number of stauromedusae in the mid-20th century.