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Published: 2022-09-22

Fragilaria pinnata var. subcapitata Frenguelli, typification and current taxonomic status

División Ficología “Dr. Sebastián A. Guarrera”, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata. Paseo del Bosque s/n, B1900FWA, La Plata, Argentina
División Ficología “Dr. Sebastián A. Guarrera”, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata. Paseo del Bosque s/n, B1900FWA, La Plata, Argentina
Water Laboratory, University of Évora, P.I.T.E. Rua da Barba Rala No. 1, 7005–345 Évora, Portugal; Institute of Earth Sciences - ICT, University of Évora, Rua Romão Ramalho 59, 7000–671 Évora, Portugal
araphid diatoms Fragilariaceae Frenguelli Collection Staurosirella taxonomy type material valve morphology Algae


Type material of Fragilaria pinnata var. subcapitata Frenguelli, a diatom originally described from diatomite in northern Chile, has been examined using light and scanning electron microscopy. Its valve morphology is described and comparisons to the original description, additional reports and closely related taxa are provided. Morphological features of this taxon confirm its transfer to the genus Staurosirella as S. subcapitata. Since Frenguelli did not formally designate a type, we selected one of the examined specimens as lectotype.


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