FLOWERING AND GENETIC BANDING-PATTERNS OF HALOPHILA-JOHNSONII AND CONSPECIFICS

Halophila johnsonii Eiseman is a seagrass that is restricted in distri bution to the Indian River of Florida from Sebastian Inlet on the nort h to Biscayne Bay on the south, and currently is being considered for listing as a rare/endangered species by the National Marine Fisheries Service (NMFS), At the time it was described as a new species in 1980, no staminate flowers had been reported. After numerous searches in th e Indian River in the late 1980s and early 1990s and after culture in the laboratory, only pistillate flowers are known. DNA testing indicat es that H. johnsonii is distinct from H. decipiens Ostenfeld. Isozymes and sulfated flavonoids had suggested earlier that H. johnsonii may b e closely related to the small-leafed plants in H. minor (Zoll.) den H artog complex that are widely distributed in the Indo-Pacific. H. john sonii may represent the vegetative development of a single pistillate clone. (C) 1997 Elsevier Science B.V.