Pennatulacea with heart-shaped rachis containing all
siphonozooids and autozooids on the dorsal surface. The stalk contains
neither an axis nor polyps.
This family is represented by one species in the South Atlantic
Bight, Renilla reniformis
Deichmann (1936) divided this taxon into two forms, americana
and typica based on saturation of colony and sclerite color.
Colonies found on the coast of the Carolinas and north Florida
are pale purple (forma typica) whereas
those off the coast of South America are darker andmore violet
(forma americana). Bayer (1961) disputed this division,
finding both pale and dark colonies in the Antilles. Both forms have been recorded in the South Atlantic