Nitzschia imae sp. nov. (Bacillariophyta, Nitzschiaceae) from Iceland, with a redescription of Hannaea arcus var. linearis

Abstract

From field-collected samples, two Icelandic diatom species were studied under light and electron microscopy, resulting in a newly described species and an emended description with a nomenclatural status change. A discussion on the morphological features of these taxa and their taxonomic affinities with related species is presented. Nitzschia imae is described from Blue Lagoon, south-west Iceland. The main diagnostic criteria include the presence of two differences morphotypes, one with obtusely rounded apices and the other with slightly asymmetrical valve outline and broadly rounded apices. Additionally, we propose an emended description for Hannaea arcus var. linearis since there is no concordance between morphometric features in the protologue and the type illustration.

Keywords

• diatoms
• new taxon
• new combination
• nitzschia
• hannaea
• iceland
• geothermal lake