Large-cell, motile, free living Nitzschiarectilonga is a marine and brackish-marine benthic diatom.It is fairly frequent and abundant on a marine littoral in temperate and tropical waters.N.rectilonga isolated from the coast of the Gulf of Mexico in Corpus Christi (Texas, USA) was inoculated into two Petri dishes, one with pure culture of the diatom, whereas in the second one N.rectilonga was associated with very small epiphytic diatoms (2-3 μ m in size).