First records of Nanofrustulum shiloi (Lee, reimer & mcenery) round, Hallsteinsen & Paasche and Nitzschia nienhuisii sterrenburg & sterrenburg (bacillariophyceae; ochrophyta) in mexican waters

We present the first records of the diatoms Nanofrustulum shiloi and Nitzschia nienhuisii for the Mexican coasts. Observations correspond to the western Gulf of California and the northeastern Yucatán peninsula and Mexican Caribean. Morfometric and ecological data are provided together with SEM and optic microscope images. These records contribute to underline the floristic richness of diatoms in the Mexican coasts by showing the occurrence of taxa otherwise confused in previous studies, thus providing a much needed confidence to the taxonomic basis required in subsequent ecological or biogeographic studies.