| Several ultrastructural analyses of taxa belonging to the genus Thalassiosira from Argentinean coastal waters were carried out, nevertheless, the smaller fraction of the nanoplanktonic Thalassiosira was frequently overlooked. The aim of this study is to show the morphological variation of T . catharinensis, to compare material found in marine coastal waters of Anegada Bay, Province of Buenos Aires, with the material analyzed in the protologue and allied taxa, and to record the species for the frst time in Argentina, extending its distribution. |
