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

Multivariate morphometrics and image analysis were used to determine t he number of well-distinguished infrageneric taxa of reddish freshwate r Audouinella in North America. Three distinct groupings were differen tiated from 83 populations collected from Alaska and Labrador in the n orth to central Mexico and Jamaica in the south. These groupings were statistically related to seven type specimens. The following species w ere recognized: A. eugenea (SKUJA) JAO, A. hermannii (ROTH) DUBY [syn. : A. violacea (KUTZ.) HAMEL and its varieties, alpina (KUTZ.) RAB., da lmatica (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 fo und only in California, A. eugenea in warm, alkaline and high-ion wate rs of the tropical rainforest and desert-chaparral, while A. hermannii occurs widely from the boreal to south temperate and in waters with r elatively low temperatures and ion content.