Fryxelliella sepulvedana sp. nov. (Triceratiaceae, Bacillariophyta), a rare species from the Mexican Pacific coasts
Mots-clés :
Bacillariophyta, Fryxelliella sepulvedana, Mexican Pacific, taxonomy.Résumé
Fryxelliella sepulvedana n. sp., from the Mexican Pacific coasts is the second species hitherto known for the genus. As in the other Fryxelliella species, F. sepulvedana has a sipho marginalis
bearing triangular apertures, three ocelli and three rimoportulae equidistantly placed near the margin of the valve. The ocelli are the most important diagnostic features of F. sepulvedana as they are large (3.5-5.0 μm in diameter) and are located in the submarginal region, at least four areolae distant from the valve margin. They differ from those of F. floridana, the other species in the genus, where the ocelli are marginal and are in contact with the sipho marginalis. While F. floridana was found in the Atlantic Ocean, F. sepulvedana was recorded in the eastern tropical Pacific. The new species was found in different coastal localities of Mexican Pacific Ocean, all close to the coast, and sampled in the water column.
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Références
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