Gyrosigma Hassall


Frustules biraphid, symmetrical to the apical and transapical axes, valves sigmoid, raphe sigmoid with external proximal raphe ends recurved in opposite directions form one another. Axial area narrow, central area round to elliptical. Punctate striae form rows perpendicular and parallel to the axial area.

A genus of benthic species, often found in mats floating up form the bottoms of lakes and reservoirs.

Light Microscope Image(s)

Each image is accompanied by the genus and species, California Academy of Sciences slide number (ie. CAS 612010), location of the specimen on the slide, and dimension in microns.