Coeloplana waltoni, a new species of minute benthic ctenophore (Ctenophora: Platyctenida) from south Florida

A minute and abundant species of benthic ctenophore is described, resurrected from an unpublished manuscript of Frederick M. Bayer (deceased). It is an ectosymbiont of octocorals in south Florida. Members of the ctenophoran order Platyctenida were unknown from American waters until 1945, when specimens from Miami, Florida were reported by F. G. Walton Smith and referred to the genus Coeloplana. That species subsequently was found in Jamaica, and Rankin (1956) described it under the new generic name Vallicula. A second species of creeping ctenophore was found in the 1960s and rediscovered in 2011, living as an ectosymbiont on octocorals in the coastal waters near Miami. This species belongs to the original genus Coeloplana and is here described as Coeloplana waltoni, new species. This description is based on specimens examined by F. M. Bayer in the 1960s and additional material from collections obtained in 2012-2013. Critical differences between C. waltoni and Vallicula multiformis are noted, based on recently collected specimens of the latter in Biscayne Bay, Miami, Florida.