Hemionitis | |
---|---|
Hemionitis palmata in the Botanical Garden Munich-Nymphenburg | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Division: | Polypodiophyta |
Class: | Polypodiopsida |
Order: | Polypodiales |
Family: | Pteridaceae |
Subfamily: | Cheilanthoideae |
Genus: | Hemionitis L. [1] |
Species | |
Hemionitis is a genus of ferns in the subfamily Cheilanthoideae of the family Pteridaceae. [1] Its circumscription varies greatly in different systems of fern classification. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), it was one of more than 20 genera in the subfamily Cheilanthoideae, and was said to have five species. [1] Other sources treat it as the only genus in the subfamily, and so accept about 450 species. [2] With the restricted circumscription, species are native to tropical America. [1]
The genus Hemionitis was first described by Carl Linnaeus in 1753. [3] The genus name is pre-Linnaean, being used for example in the Hortus Cliffortianus , [4] and derives from the Greek word ἡμίονος (hemionos), meaning 'mule', referring to the belief that the plants were sterile. [5] (Linnaeus used the same word in the name " Asplenium hemionitis ".)
The division of the subfamily Cheilanthoideae into genera varies greatly between sources as of January 2020 [update] . Christenhusz et al. (2011), the Pteridophyte Phylogeny Group classification of 2016 (PPG I), and the Checklist of Ferns and Lycophytes of the World divide the subfamily into 20 or more genera, of which one is Hemionitis sensu stricto. [6] [1] [7] On the other hand, Christenhusz et al. (2018) and Plants of the World Online use Hemionitis sensu lato as a catch-all genus for the subfamily, resulting in about 450 species. [8] [2]
Using the PPG I approach, as of January 2020 [update] , the Checklist of Ferns and Lycophytes of the World accepted the following species (and one hybrid) in Hemionitis sensu stricto. All are native to tropical America. [7]
The Dryopteridaceae are a family of leptosporangiate ferns in the order Polypodiales. They are known colloquially as the wood ferns. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the family is placed in the suborder Polypodiineae. Alternatively, it may be treated as the subfamily Dryopteridoideae of a very broadly defined family Polypodiaceae sensu lato.
Lycopodium is a genus of clubmosses, also known as ground pines or creeping cedars, in the family Lycopodiaceae. Two very different circumscriptions of the genus are in use. In the Pteridophyte Phylogeny Group classification of 2016, Lycopodium is one of nine genera in the subfamily Lycopodioideae, and has from nine to 15 species. In other classifications, the genus is equivalent to the whole of the subfamily, since it includes all of the other genera. More than 40 species are accepted.
Polypodiaceae is a family of ferns. In the Pteridophyte Phylogeny Group classification of 2016, the family includes around 65 genera and an estimated 1,650 species and is placed in the order Polypodiales, suborder Polypodiineae. A broader circumscription has also been used, in which the family includes other families kept separate in PPG I. Nearly all species are epiphytes, but some are terrestrial.
The Cyatheaceae are a family of ferns, the scaly tree ferns, one of eight families in the order Cyatheales in the Pteridophyte Phylogeny Group classification of 2016. Alternatively, the family may defined much more broadly as the only family in the Cyatheales, with the PPG I family treated as the subfamily Cyatheoideae. The narrower circumscription is used in this article.
Pteridaceae is a family of ferns in the order Polypodiales, including some 1150 known species in ca 45 genera, divided over five subfamilies. The family includes four groups of genera that are sometimes recognized as separate families: the adiantoid, cheilanthoid, pteridoid, and hemionitidoid ferns. Relationships among these groups remain unclear, and although some recent genetic analyses of the Pteridales suggest that neither the family Pteridaceae nor the major groups within it are all monophyletic, as yet these analyses are insufficiently comprehensive and robust to provide good support for a revision of the order at the family level.
Blechnum, known as hard fern, is a genus of ferns in the family Blechnaceae, subfamily Blechnoideae, according to the Pteridophyte Phylogeny Group classification of 2016. Two very different circumscriptions of the genus are used by different authors. In the PPG I system, based on Gasper et al. (2016), Blechnum is one of 18 genera in the subfamily Blechnoideae, and has about 30 species. Other sources use a very broadly defined Blechnum s.l., including accepting only two other genera in the subfamily. The genus then has about 250 species. In the PPG I circumscription, the genus is mostly neotropical, with a few southern African species.
Aleuritopteris is a genus of ferns in the Cheilanthoideae subfamily of the Pteridaceae. As with some other genera of the Cheilanthoideae, molecular phylogenetic studies have suggested that it is not monophyletic, and so may need to be circumscribed differently in future.
Thelypteris is a genus of ferns in the subfamily Thelypteridoideae, family Thelypteridaceae, order Polypodiales. Two radically different circumscriptions of the genus are in use as of January 2020. In the Pteridophyte Phylogeny Group classification of 2016, the genus is a very small one with about two species. In other approaches, the genus is the only one in the subfamily Thelypteridoideae, and so includes between 875 and 1083 species.
The Lomariopsidaceae is a family of ferns with a largely tropical distribution. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the family is placed in the suborder Polypodiineae of the order Polypodiales. Alternatively, it may be treated as the subfamily Lomariopsidoideae of a very broadly defined family Polypodiaceae sensu lato.
Schizaeaceae is a family of ferns in the order Schizaeales. In the Pteridophyte Phylogeny Group classification of 2016, it includes only two genera. Alternatively, two families kept separate in PPG I, Lygodiaceae and Anemiaceae, may be included in Schizaeaceae so that the family has four genera. In this approach, the Schizaeaceae of PPG I is treated as the subfamily Schizaeoideae.
Tectariaceae is a family of leptosporangiate ferns in the order Polypodiales. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the family is placed in the suborder Polypodiineae. Alternatively, it may be treated as the subfamily Tectarioideae of a very broadly defined family Polypodiaceae sensu lato. The family comprises seven genera, of which Tectaria is by far the largest.
Microsoroideae is a subfamily in the fern family Polypodiaceae in the Pteridophyte Phylogeny Group classification of 2016 (PPG I). The subfamily is also treated as the tribe Microsoreae within a very broadly defined family Polypodiaceae sensu lato. In either treatment, it includes the previously separated tribe Lepisoreae.
Polypodioideae is a subfamily belonging to the fern family Polypodiaceae, which is a member of the suborder Polypodiineae in the Pteridophyte Phylogeny Group classification of 2016 (PPG I). Alternatively, the subfamily may be treated as the tribe Polypodieae within a very broadly defined family Polypodiaceae sensu lato.
Hemidictyum is a genus of ferns with a single species, Hemidictyum marginatum, commonly known as the marginated half net fern. In the Pteridophyte Phylogeny Group classification of 2016, it is the only genus in the family Hemidictyaceae. Alternatively, the family, along with Aspleniaceae sensu stricto, may be placed in a much more broadly defined family Aspleniaceae as the subfamily Asplenioideae.
Drynarioideae is a subfamily of the fern family Polypodiaceae in the Pteridophyte Phylogeny Group classification of 2016 (PPG I). The subfamily is also treated as the tribe Drynarieae within a very broadly defined family Polypodiaceae sensu lato. In either case, it includes the previously separated tribe Selligueeae.
Vittarioideae is a subfamily of the fern family Pteridaceae, in the order Polypodiales. The subfamily includes the previous families Adiantaceae and Vittariaceae.
Cheilanthoideae is one of the five subfamilies of the fern family Pteridaceae. The subfamily is understood to be monophyletic, but some of the genera as currently defined are not. Most species are xeric-adapted, and the subfamily is most diverse in dry areas.
Doryopteris is a genus of ferns in the subfamily Cheilanthoideae of the family Pteridaceae.
Draconopteris is a genus of ferns in the family Tectariaceae, with a single species Draconopteris draconoptera, according to the Pteridophyte Phylogeny Group classification of 2016 (PPG I).
Malaifilix is a genus of ferns in the family Tectariaceae, with a single species Malaifilix grandidentata, according to the Pteridophyte Phylogeny Group classification of 2016 (PPG I).