Polypodiineae is a suborder of
ferns in the order
Polypodiales
The Order (biology), order Polypodiales encompasses the major lineages of polypod ferns, which comprise more than 80% of today's fern species. They are found in many parts of the world including Tropics, tropical, semitropical and Temperate clima ...
. It is equivalent to the
clade
In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...
eupolypods I in earlier systems,
[ and to the very broadly defined family Polypodiaceae in the classification of Christenhusz & Chase (2014).][ It probably diverged from the suborder Aspleniineae (eupolypods II) during the mid-Cretaceous. The divergence is supported by both molecular data and an often overlooked morphological characteristic which lies in the vasculature of the petiole. Most species that make up the suborder 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).][
]
Taxonomy
In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the group is treated as the suborder Polypodiineae, and divided into 11 families.[ Alternatively, it may be treated as a single, very broadly circumscribed family Polypodiaceae '' sensu lato'', which is then divided into subfamilies.][ The relationship between the two approaches is shown in the table below.
]
Phylogeny
The Polypodiineae is one of two major groups of eupolypod families, treated as suborders, within the order Polypodiales
The Order (biology), order Polypodiales encompasses the major lineages of polypod ferns, which comprise more than 80% of today's fern species. They are found in many parts of the world including Tropics, tropical, semitropical and Temperate clima ...
. In 2016, the Pteridophyte Phylogeny Group published a consensus cladogram
A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...
, based on "numerous phylogenetic studies" between 2001 and 2015. The location of the Polypodiineae within the order Polypodiales in this cladogram is:[
To the level of families, the subtree for the Polypodiineae is:][
Of the 108 genera in the suborder, 91 (84%) are placed in two families, Dryopteridaceae and Polypodiaceae.][
]
References
{{Taxonbar, from1=Q30110526, from2=Q5410882
Polypodiales