DISTRIBUTION AND SYSTEMATICS OF BATRACHOSPERMUM(BATRACHOSPERMALES, RHODOPHYTA) IN NORTH AMERICA. 6. SECTION TURFOSA1

Abstract

ABSTRACTTwenty‐one populations of Batrachospermum section Turfosa from North America were compared to nine type and two historically important specimens using multivariate morphometrics and image analysis. The protologues of six other infrageneric taxa were also compared. From this analysis, six species are recognized worldwide: B, de‐sikacharyi Sankaran, B. gombakense Kumano et Ratnasabapathy, B. keratophytum Bory de Saint‐Vincent [syn. B. vagum var. keratophytum (Bory de Saint‐Vincent) Sirodot, B. gulbenkianum Reis, and B. suevorum Kützing nom. Meg.], B. sinense Jao, B. turfosum Bory de Saint‐Vincent [syn. B. vagum (Roth) C. Agardh and B. vagum var. undulato‐pedicellatum Kumano et Watanabe], and B. vogesiacum F. G. Schultz ex Skuja [syn. B. vagum var. flagelliforme Sirodot, B. flagelliforme (Sirodot) Necchi], These species are distinguished on the basis of carposporophyte‐bearing branch cortication, secondary fascicle development, monoecy or dioecy, presence of spermatangia on involucral filaments and monosporangia, and dimensions of trichogynes and carposporangia. Peripheral cortication has been previously used to separate species in this section, but we observed that this feature is quite widespread in the section. Presence of indeterminate gonimoblast filaments has been reported for some taxa in section Turfosa, but no such structures were seen in any of the specimens examined. Only B. keratophytum has been collected in North America, ranging from southwestern Greenland (64°N) to Louisiana (30° N).