Corallophila eatoniana comb. nov. (Ceramiaceae, Rhodophyta) from the Pacific coast of North America

Abstract

A new combination is proposed for plants previously referred to as Ceramium eatonianum (Farlow) De Toni [= Centroceras eatonianum Farlow 1875] (Ceramiaceae, Rhodophyta). This red algal species is transferred to the genus Corallophila mostly on the basis of the following characteristics. It has rhizoids that arise from periaxial and inner cortical cells, outer cortical cells that are rectangular and arranged in longitudinal rows, spermatangia that develop on ordinary cortical cells, and tetrasporangia that are covered by cortical cells. Corallophila eatoniana is further characterized by having uniseriate rhizoids, pinnate branches. six to eight (usually seven) periaxial cells at the nodes, large gland cells on the tips of acropetal cortical filaments, and tetrasporangia on the upper parts of regular branches. The species occurs on the Pacific coast of North America from British Columbia, Canada, to Baja California, Mexico. Corallophila eatoniana is here neotypified by a specimen collected at Seal Rock, Oregon, on 10 July 1998. Generic comparisons between Corallophila and the fully corticated species of Ceramium and Centroceras are also given.