Eupolypods I

Eupolypods I
Common Polypody, Polypodium vulgare
Scientific classification
Kingdom: Plantae
Division: Pteridophyta
Class: Polypodiopsida/Pteridopsida
(disputed)
Order: Polypodiales
(unranked): Eupolypods
(unranked): Eupolypods I
Families

Polypodiaceae
Davalliaceae
Oleandraceae
Tectariaceae
Lomariopsidaceae
Dryopteridaceae
Elaphoglossaceae
Hypodematiaceae

Eupolypods I is a clade of ferns in the order Polypodiales[1]. It probably diverged from Eupolypods II during the mid-Cretaceous. The divergence is supported by both molecular data and an often over-looked morphological characteristic which lies in the vasculature of the petiole. Most species that make up the Eupolypods I clade have three vascular bundles. The only exceptions are the Grammitid ferns which have one, and the genus Hypodematium which has two. This differs from Eupolypods II which mostly have two vascular bundles (except the well-nested blechnoid ferns which generally have at least three).[2]

References

  1. ^ Smith, A. R., K. M. Pryer, et al. (2006). "A classification for extant ferns." Taxon 55(3): 705-731
  2. ^ S. Blair Hedges; Sudhir Kumar (2009). The Timetree of Life. US: Oxford University Press. pp. 154–156. http://books.google.com/books?id=9rt1c1hl49MC. Retrieved 23 August 2011.