Other taxa possess the characteristic cruciform shape of S. construens, but differ in several regards. Staurosira incerta differs by its smoother central inflation, longer lineolae, apical pore fields located on the valve mantle, and ribbon-like siliceous deposits on the abvalvar side of the mantle. Staurosirella leptostauron has more heavily silicified valves and longer lineolae, creating broader striae. Pseudostaurosira pseudoconstruens has a wider central sternum and round areolae.