Below is the flora of the La Colonia Formation, as it is presently understood. The classification of the angiosperms follows Chase and Reveal (2009. Bot. J. Linn. Soc. 161: 122-127); and of ferns, Christenhusz et al. (2011. Phytotaxa 19: 7-54). Sources: A. Archangelsky et al. (1999), Gandolfo & Cúneo (2003-abstract, 2005, 2009-abstract), Hermsen et al. (2012-abstract), Gallego et al. (2012-abstract), and Cúneo et al. (in press).
FERNS
Subclass: Polypodiidae
Order: Cyatheales
Family: Dicksoniaceae
Dicksoniaceae sp., Cañadón del Irupé, fertile leaves (undescribed)
Order: Hymenophyllales
Family: Hymenophyllaceae
Hymenophyllaceae sp., leaves (undescribed)
Order: Salviniales (aquatic ferns)
Family: Marsileaceae
Marsileaceae sp., Cañadón del Irupé, leaves (undescribed)
Marsileaceae sp., Cañadón del Irupé, sporocarps (undescribed)
Crybelosporites cf. pannuceus (Brenner) Srivastava, Cerro Bosta, microspores
Molaspora lobata (Dijkstra) Hall, Cerro Bosta & Cañadón del Irupé, megaspores
Regnellidium sp., Cerro Bosta & Quebrada del Helecho, rhizomes, roots, leaves (undescribed)
Family: Salviniaceae
Paleoazolla patagonica A. Archangelsky et al., Cerro Buitre, megaspore complexes, microspore massulae.
Order: Salviniales
Family: Salviniaceae
Azolla sp. TY004, leaves (undescribed)
SPERMATOPHYTA
Subclass Magnoliidae (the angiosperms)
Superorder: Lilianae (monocots)
Clade: Commelinids
Order: Arecaceae
Family: Arecaceae
Araceae sp., Cañadón del Irupé, leaves (undescribed)
Order: Poales
Family: Typhaceae
Typhaceae sp., leaves (undescribed)
Superorder: Nymphaeanae
Order: Nymphaeales
Family: Nymphaeaceae (water lilies)
Nympheaeceae sp., seeds (undescribed)
Clade: Eudicots
Superorder: Proteanae
Order: Proteales
Family: Nelumbonaceae (lotuses)
Nelumbo sp., Cañadón del Irupé, fruit-receptacles & fruits
Nelumbo puertae Gandolfo & Cúneo, Cañadón del Irupé, leaves
Dicots—affinities uncertain
Five morphotypes (undescribed)