First record of Capartogramma paradisiaca Novelo, Tavera & Ibarra (Diatomeae) in South America

The most distinctive feature of Capartogramma Kufferath is the x-shaped thickening of silica at valve center, namely the tigillate stauro. In addition, pseudosepta at the valve apices and uniseriate striae composed by rounded areolae characterize the genus. Seven species have been described to date, including Capartogramma paradisiaca Novelo, Tavera & Ibarra which were only found in Mexico. The morphology of C. paradisiaca was studied using light and electron microscopy and was compared with similar species. C. paradisiaca is reported for the first time in South America at Paraiso Beach, Northern Brazil, where it was found as episammic periphyton. Also, we provided unprecedented frustule ultrastructural details of the studied species.