Fragilariforma meireana, a new araphid diatom species (Bacillariophyta) producing internal valves from Flanders

During a biodiversity survey around the historic Flemish town of Damme, a large Fragilariforma taxon was observed in a small pond that could not be identified using the currently available literature. Detailed light and scanning electron microscopy investigations revealed the presence of so-called resting spores within the frustules. Following comparison with similar linear, long-celled Fragilariforma species, the unknown taxon is described as new: Fragilariforma meireana sp. nov.

Discriminating features of the new species include the long, linear valves with protracted, distinctly rostrate apices, the absence of ribbon-like colonies, the presence of a rimoportula on both apices and the formation of internal resting spores.