Fractofusus misrai is an extinct deep sea rangeomorph that lived during the Ediacaran period (~ 560 Mya). It grew up to 220mm in length and was one of the first complex multi-cellular organisms to appear on Earth.
First reported by Anderson and Misrai in 1968, Fractofusus was discovered at Mistaken Point in Newfoundland. Fractofusus has a flat spindle-shaped body (fusiform) that consisted of two vanes divided by a zig-zag commissure. Each vane was made up of a series of oblong modules that were in turn made up of distinctive fractal-branching frondlets (Gehling & Narbonne, 2007).
Fractofusus is identified as a rangeomorph which are understood to have been benthic organisms that existed in the deep ocean away from sunlight - which means that they could not have been a form of photosynthesising plant. The fractal nature of rangeomorph morphology also precludes them from being classified as early animals so they remain something of a taxonomic mystery.
Statistical studies of distributional patterns suggest that Fractofusus reproduced by growing tendrils out from the parent body that then terminated in sprouting offspring (Mitchell E, et al, 2015). These tendrils are known as stolons and are usually associated with plants.
Rangeomorphs became extinct prior to the Cambrian Explosion of animal life - before the appearance of most phyla that we know today. It is not known how they became extinct but one hypothesis is that, being sedentary, they were easy prey for newly evolving basal animals that were becoming motile and able to move about the environment.
With thanks to Dr Jean-Bernard Caron for feedback on anatomical detail.
