Topical observations on centric diatoms (Bacillariophyceae, Centrales) of Lake Como (N. Italy)

Abstract

In 2001 a qualitative analysis of the centric diatoms in Lake Como was made. In this work 15 taxa of the genus of Stephanodiscus. Cyclotella, Melosira. Aulacoseira and Stephanocostis were recorded. Among them the taxa Cyclotella pseudostelligera, C. comensis, C. comensis morphotype minima, C. costei, Stephanodiscus minutulus and Stephanocostis chantaicus were of special interest to us with regard to their morphological and taxonomical features. Morphological variability as well as taxonomical classification is discussed. A short appraisal of the ecological state of the Lake Como is given. Without any further critical considerations all centric taxa of Lake Como recorded from fossil to up-to-date collections are compiled.