Original Article

Plant Systematics and Evolution

, Volume 300, Issue 2, pp 369-386

First online:

New marsileaceous fossils from the Late Cretaceous of South America and a reevaluation of Marsileaceaephyllum

  • Elizabeth J. HermsenAffiliated withDepartment of Environmental and Plant Biology, Ohio University Email author 
  • , María A. GandolfoAffiliated withDepartment of Plant Biology, Cornell University
  • , N. Rubén CúneoAffiliated withMuseo Paleontológico Egidio Fergulio-CONICET

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access


Herein we report new macrofossils and associated microfossils representing the aquatic fern family Marsileaceae from the Campanian to Maastrichtian Cañadón del Irupé locality, La Colonia Formation, Chubut Province, Argentina. The macrofossils include compound leaves, detached leaflets, and sporocarps. The venation of the leaflets is consistent with the diagnosis of Marsileaceaephyllum, which we argue is poorly defined. Consequently, the circumscription and diagnosis of Marsileaceaephyllum are emended in order to limit the taxon to include only leaves or rhizomes bearing leaves with four leaflets that most resemble those of Marsilea among extant genera of Marsileaceae. The Cañadón del Irupé leaves and leaflets are assigned to the new genus Mirasolita, erected to encompass compound leaves bearing two petiolulate leaflets, each leaflet having a reniform lamina and reticulate venation. The architecture of Mirasolita leaves and leaflets is distinct from that of leaves of any of the living marsileaceous genera. The stalked sporocarps are assigned to the new genus Lugiomarsiglia. They are attributed to Marsileaceae because each has a sclerenchymatous wall surrounding circular bodies interpreted as sporangia. Associated megaspores are assigned to Molaspora lobata, a geographically widespread, primarily Late Cretaceous dispersed spore taxon. The co-occurrence of Molaspora lobata with an extinct marsileaceous leaf form fits a pattern wherein Cretaceous Regnellidium-like megaspores are associated with or found in situ within marsileaceous macrofossils that display a variety of morphologies.


Cretaceous fossil La Colonia Formation Marsileaceae Patagonia