SYSTEMATICS OF FRESH-WATER AUDOUINELLA (ACROCHAETIACEAE, RHODOPHYTA) IN NORTH-AMERICA .1. THE REDDISH SPECIES

Multivariate morphometrics and image analysis were used to determine the number of well-distinguished infrageneric taxa of reddish freshwater Audouinella in North America. Three distinct groupings were differentiated from 83 populations collected from Alaska and Labrador in the north to central Mexico and Jamaica in the south. These groupings were statistically related to seven type specimens. The following species were recognized: A. eugenea (SKUJA) JAO, A. hermannii (ROTH) DUBY [syn.: A. violacea (KUTZ.) HAMEL and its varieties, alpina (KUTZ.) RAB., dalmatica (KUTZ.) RAB., expansa (WOOD) SMITH, and hercynica (KUTZ.) KUTZ.] and A. tenella (SKUJA) PAPENFUSS. These species are separated based on dimensions of vegetative cells and monosporangia. A. tenella is found only in California, A. eugenea in warm, alkaline and high-ion waters of the tropical rainforest and desert-chaparral, while A. hermannii occurs widely from the boreal to south temperate and in waters with relatively low temperatures and ion content.