Compare Pseudostaurosira americana

Pseudostaurosira americana is often misidentified as P. subsalina, however, P. subsalina has not yet been confirmed in North America. Pseudostaurosira americana is distinguished by a narrow sternum and stria density (16-18 in 10 µm). Pseudostaurosira subsalina, in contrast, possesses a slightly broader, lanceolate sternum and the stria density is lower. Other taxa should also be compared: P. alvareziae has a lower stria density (13-15 in µm) than P. americana. Pseudostaurosira neoelliptica is more narrow than P. americana (3-4 µm to 4.5-5.0, respectively) and P. neoelliptica also has a lower stria density (12-15 in 10 µm). Several undescribed species are known to be present in North America.