Publication: Bot. Gaz. 33: 66. 1902.
selected vouchers: WTU
Notes: FNA2: "Marsilea oligospora recently has been resegregated from M . vestita (D. M. Johnson 1986), from which it differs consistently in its nodding sporocarps that lack a pronounced distal tooth and its pilose leaves and stems. Where their ranges overlap, M . oligospora also has longer sporocarp stalks than does M . vestita . Plants of this species were recently grown from spores 100 years old (D. M. Johnson 1985)."