Viridiella fridericiana (Chlorococcales, Chlorophyta), a new genus and species isolated from extremely acid environments

Abstract

The genus Viridiella gen. nov. with a single species Viridiella fridericiana sp. nov. (Chlorococcales, Chlorophyta) is proposed. Cells are ellipsoidal to globose, and have a smooth cell wall and a single parietal chloroplast without pyrenoids. Reproduction occurs by the formation of 4–8 autospores. Viridiella can be distinguished from the closely related genus Chiorella by its cell wall ultrastructure and the absence of pyrenoids. The cellulosic cell wall is composed of a single layer with an irregular outer polysaccharide covering. Interthylakoidal starch grains are present. Viridiella fridericiana is extremely tolerant of low pH, being capable of growth at pH 0.8–7.2.