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Todea (family Osmundaceae) A monotypic genus (T. barbata) of primitive ferns, which, like Osmunda, has certain features that are intermediate between the ancient eusporangiate and the modern leptosporangiate ferns: more than 1 initial cell may contribute to the formation of each sporangium and more than 500 spores may be produced in each one, but the sporangia are stalked. Todea produces its thick-stalked sporangia on the under-surface of the fronds only, and not aggregated into sori, while in Osmunda the sporangia are borne in marginal clusters on certain pinnae. T. barbata is found in the temperate regions of the Old World southern hemisphere.