Tetracyclus hinziae (Bacillariophyta), a new species from the central Cascade Mountains (WA, USA)

摘要

Here we describe a new freshwater diatom species from the Cascade Mountain Range in Washington State, including observations of living cells and chloroplast structure. The species represents the fourth known extant species within the genus, as most species of Tetracyclus Ralfs are extinct. The new species can be distinguished from other Tetracyclus species and Diatoma mesodon Kutzing by its lanceolate-elliptical shape, apiculate ends, small size, rimoportula placement, and distinct septa pattern. The distribution of the new taxon is currently catchments within the Mt. Baker-Snoqualmie National Forest and Mount Rainier National Park, and is found in greatest abundance in aerophilous, moss and liverwort habitats in first-and second-order streams.