rangeomorph

Noun

 * 1) Any organism of the clade, Precambrian (Ediacaran) sessile organisms resembling ferns, possibly descended from sponges and among the oldest known complex lifeforms.

Usage notes
Despite their showing few characteristics of animals, it remains an open question whether to classify rangeomorphs within kingdom Animalia or, if not an entirely different group of protists that independently evolved multicellularity. They are in any case presumed to have gone extinct without leaving modern descendants.