Hyalogramma M.Garcia (Fragilariales, Bacillariophyceae): a new hyaline araphid genus from Brazilian marine sandy beaches

Abstract

Observation of sand samples collected from dissipative marine sandy beaches in Southern Brazil revealed the presence of a new hyaline araphid diatom, characterized by the presence of two rimoportulae per frustule (located in a diagonal position at each apex), two simple apical pore fields on the mantle at each valve pole, striae that are not visible in LM, a very narrow sternum visible only in SEM, and open and similar bands ornamented by 3–5 rows of poroids. The new species, Hyalogramma brasiliensis M.Garcia, belongs to a new araphid genus, Hyalogramma M.Garcia, and is placed within the family Fragilariaceae.