PERIPHYTON FLORA OF SOME LOTIC AND LENTIC ENVIRONMENTS OF HOPE BAY (ANTARCTIC PENINSULA)

A taxonomic study was made of the periphytic algal flora of some fresh water environments at Hope Bay, Antarctic Peninsula (63 degrees 27'S; 56 degrees 59'W), during summer 1992-1993. Seven lakes and two pools t hat are characterized by different trophic levels were studied. The la rgest, Boeckella Lake, has an important outflow (Prasiola Stream) that was also analyzed. Ninety-seven algal taxa, including specific and in fra-specific entities, are recorded. Thirty-one new records for the An tarctic continent are described and illustrated. The flora comprises 4 4.4% Cyanophyceae, 21.6% Bacillariophyceae, 18.5% Chlorophyceae, 9.3% Tribophyceae, 4.2% Chrysophyceae and 2% Zygophyceae. The epilithic flo ra of Hope Bay shows a high species richness. Phormidium fragile and L yngbya lagerheimii were the most abundant species among the Cyanophyce ae. In the algal mats we Chrysophyceae (mainly Hydrurus foetidus Chrys ococcus rufescens) and the macroscopic chlorophycean Prasiola crispa. Tribonema australis sp. nov. (Tribonematales, Tribophyceae) is put for ward as a new species. Hormidium fluitans (Gay) Heering is renamed Kle bshormidium fluitans.