Data from: Anatomy of the Ediacaran rangeomorph Charnia masoni

The Ediacaran macrofossil Charnia masoni Ford is perhaps the most iconic
member of the Rangeomorpha: a group of seemingly sessile, frondose
organisms that dominates late Ediacaran benthic, deep‐marine fossil
assemblages. Despite C. masoni exhibiting broad palaeogeographical and
stratigraphical ranges, there have been few morphological studies that
consider the variation observed among populations of specimens derived
from multiple global localities. We present an analysis of C. masoni that
evaluates specimens from the UK, Canada and Russia, representing the
largest morphological study of this taxon to date. We describe substantial
morphological variation within C. masoni and present a new morphological
model for this species that has significant implications both for
interpretation of rangeomorph architecture, and potentially for existing
taxonomic schemes. Previous reconstructions of Charnia include assumptions
regarding the presence of structures seen in other rangeomorphs (e.g. an
internal stalk) and of homogeneity in higher order branch morphology;
observations that are not borne out by our investigations. We describe
variation in the morphology of third and fourth order branches, as well as
variation in gross structure near the base of the frond. The diagnosis of
Charnia masoni is emended to take account of these new features. These
findings highlight the need for large‐scale analyses of rangeomorph
morphology in order to better understand the biology of this
long‐enigmatic group.