OBSERVATIONS AND REMARKS ON MORPHOLOGY AND TAXONOMY OF THE DIATOM GENERA GYROSIGMA HASSALL AND PLEUROSIGMA W. SMITH IV. GYROSIGMA FOGEDII SP. NOV., AND SOME DIATOMS SIMILAR TO G. FASCIOLA (EHRENB.) GRIFFITH & HENFREY

Abstract

Gyrosigma fogedii sp. nov., from coastal marine habitats in North Island and South Island, New Zealand, is described. This species bears some resemblance to Gyrosigma fasciola but can be distinguished from the latter by its spathulate apices and dichotomous/intercalary striae opposite the central valve area. Studies of G. fogedii have been made by light microscopy (LM) and scanning electron microscopy (SEM). Studies of specimens with affinities to G. fasciola have been by LM only. Further studies on the type of G. fasciola and other taxa in the complex, also with SEM, will be necessary.