Halimeda renschii revived, and Halimeda batanensis (Chlorophyta, Siphonales)

Abstract

Abstract The Halimeda species renschii, described by Hauck in 1886 was considered a form of H. opuntia by Barton in her 1901 monograph of the genus. Since then there has been little apparent reference to the type description or collection of H. renschii, with the result that much of the material in herbaria assigned to H. opuntia f. renschii is not this taxon. During my continuing study of the genus Halimeda I examined the type collection of H. renschii. A comparison with typical H. opuntia revealed differences in habit, ecology and microscopic characteristics such that H. renschii should be considered a distinct species rather than a form. Rijksherbarium specimen 937,277–154 is designated the lectotype. New H. renschii material includes collections from the International Indian Ocean Expedition. The new species Halimeda batanensis W. R. Taylor was included in this study. No significant differences were found between it and H. renschii, and since the name H. renschii has priority, H. batanensis is placed ...