Cell outline long and thin (maybe somewhat curved), with green cell contents
-
Cells long, slender, slightly curvied; row of pyrenoids in chloroplast along cell length; ends are tapered but have rounded points.
Closteriopsis -
Long, spindle-shaped cells tapering to sharp points, weakly to strongly curved, row of pyrenoids absent; may cluster together in bundles.
Ankistrodesmus