''Eupodium'' is a genus of
fern
The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissue ...
s in the family
Marattiaceae native to the
Neotropics
The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropical terrestrial ecoregions of the Americas and the entire South American temperate zone.
Definition
In biogeog ...
. Traditionally, many taxonomists have included ''Eupodium'' within the genus ''
Marattia'' (along with ''
Ptisana''). However, molecular phylogenetic studies and morphological studies of extant and fossil taxa support the recognition of ''Eupodium'' as a lineage distinct from ''Marattia''.
Morphologically, ''Eupodium'' was thought to be distinct among the
Marattiaceae in only having one
frond
A frond is a large, divided leaf. In both common usage and botanical nomenclature, the leaves of ferns are referred to as fronds and some botanists restrict the term to this group. Other botanists allow the term frond to also apply to the lar ...
at a time (occasionally two), bearing awns along veins, and having stalked
synangia (clusters of sporangia that have become fused in development). However, recent phylogenetic work found that an additional species native to Brazil, ''
Eupodium cicutifolium'', which lacks these characters, is also genetically in ''Eupodium'', making the genus challenging to distinguish morphologically.
''Eupodium cicutifolium'' does occasionally have short-stalked synangia, and has spinulose spores like the other ''Eupodium'' species, but is otherwise easily mistaken for a ''Marattia'' or ''
Ptisana''. The genus currently has four recognized species.
The basal chromosome number for this genus is unknown. The type species is ''
Eupodium kaulfussii''.
Phylogeny
Phylogeny of ''Eupodium''
The genus includes the following species:
* ''
Eupodium cicutifolium''
( Kaulf.) Lehtonen (Brazil, northern Argentina)
* ''
Eupodium kaulfussii''
( J.Sm.) J.Sm. (Brazil)
* ''
Eupodium laeve''
( Sm.) Murdock (Cuba, Hispaniola, Puerto Rico)
* ''
Eupodium pittieri''
( Maxon) Christenh. (Central America, Colombia, Ecuador, Peru, Bolivia, Venezuela, Trinidad)
References
{{Fern classification
Marattiidae
Fern genera