Polypodiineae is a suborder of

fern A fern (Polypodiopsida or Polypodiophyta ) is a member of a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. The polypodiophytes include all living pteridophytes except t ...

s in the order

Polypodiales The 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 tropical, semitropical and temperate areas. Description Polypodiale ...

. It is equivalent to the

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

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 Aspleniineae is a suborder of ferns in the order Polypodiales. It is equivalent to the clade eupolypods II in earlier systems; it is also treated as a single very broadly defined family Aspleniaceae. The suborder generally corresponds with the o ...

(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 The Pteridophyte Phylogeny Group, or PPG, is an informal international group of systematic botanists who collaborate to establish a consensus on the classification of pteridophytes (lycophytes and ferns) that reflects knowledge about plant relation ...

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 In geometry, the circumscribed circle or circumcircle of a polygon is a circle that passes through all the vertices of the polygon. The center of this circle is called the circumcenter and its radius is called the circumradius. Not every polyg ...

family Polypodiaceae ''

sensu lato ''Sensu'' is a Latin word meaning "in the sense of". It is used in a number of fields including biology, geology, linguistics, semiotics, and law. Commonly it refers to how strictly or loosely an expression is used in describing any particular co ...

'', 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

. In 2016, the

published a consensus

cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ...

, 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