Contribution

Ammatoidea normanii (Cyanobacteria, Homoeotrichaceae) from La Gorce Mountains, Antarctica

Broady, Paul A.; Ingerfeld, Manfred

Abstract

Ammatoidea normanii W. et G. S. West is described for the first time in Antarctica from a single sample of mat-like growths in a rock fissure at a far south (86°30'S, 147°W), high altitude (c. 1800 m) location. The first cultures of this alga are reported. These were established on media containing low concentrations of mineral nutrients. Morphology of field specimens differed from that of material grown on 1/20 diluted nutrient medium BG-11 and distilled water agar. Transmission electron microscopy showed varied thylakoid patterns. The lack of heterocyte formation in low nitrogen media suggests that Ammatoidea is a valid genus. Antarctic specimens are compared with type material and other records of A. normanii. Where possible, comparison is made with other Ammatoidea species. A. normanii appears to be cosmopolitan and to have a wide ecological amplitude but further studies of new collections are required to test current species concepts within the genus.

Mots-clefs

Algae • Cyanobacteria • Antarctica • taxonomy • cultures • light microscopy • ultrastructure • distribution