Gelidiaceae (Rhodophyta) from the northern Gulf of California, Mexico

Abstract

Abstract Extensive recent collections of Gelidiaceae (Rhodophyta) from the northern Gulf of California, Mexico were studied. Comparisons of field-collected and laboratory-grown thalli support the merger of Pterocladia parva Dawson with P. caloglossoides (Howe) Dawson. Gelidium microphysa Setchell & Gardner was found to be a form of G. pusillum (Stackh.) Le Jolis. Gelidium crinale (Turn.) Gaillon ex Desmazieres, including Gulf specimens previously identified as G. crinale var. luxurians Collins, is here considered as a form of G. pusillum, in concurrence with a recent treatment of these taxa in Great Britain. Relatively well defined morphology and bilocular cystocarps clearly distinguish G. johnstonii Setchell & Gardner from other Gulf species. Cystocarps have not been found on thalli of G. sonorense Dawson and G. decompositum Setchell & Gardner, both known only from the Gulf. On the basis of vegetative characters these two species are referred to Pterocladia capillacea (Gmel.) Bornet & Thuret, a species t...