Blechnum is a genus of ferns. Two very different circumscriptions of the genus are used by different authors. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), Blechnum is one of 18 genera in the subfamily Blechnoideae of the family Blechnaceae, and has about 30 species. [1] Other sources place many more species in the genus, with only two other genera in the subfamily. The genus then has about 250 species. [2]
Species placed in Blechnumas of December 2019 [update] by Plants of the World Online , which uses the broad circumscription, but transferred to other genera by the Checklist of Ferns and Lycophytes of the World, which uses the narrow circumscription, are listed below together with their alternative placement. [3] [4]
Cyathea is a genus of tree ferns, the type genus of the fern order Cyatheales.
Onoclea is a genus of plants in the family Onocleaceae, native to moist habitats in eastern Asia and eastern North America. They are deciduous ferns with sterile fronds arising from creeping rhizomes in spring, dying down at first frost. Fertile fronds appear in late summer. Depending on the authority, the genus contains one to five species.
Blechnaceae is a family of ferns in the order Polypodiales, with a cosmopolitan distribution. Its status as a family and the number of genera included have both varied considerably. In the Pteridophyte Phylogeny Group classification of 2016, the family has 24 genera, and excludes genera placed in the separate family Onocleaceae. The family is divided into three subfamilies, including Blechnoideae s.s. Alternatively, the entire family may be treated as the subfamily Blechnoideae s.l. of a very broadly defined family Aspleniaceae, and include genera others place in Onocleaceae.
Lomaria is a genus of ferns belonging to the family Blechnaceae.
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.
Pleopeltis is a genus of ferns in the family Polypodiaceae, subfamily Polypodioideae, according to the Pteridophyte Phylogeny Group classification of 2016 (PPG I). The genus widely distributed in tropical regions of the world, and also north into temperate regions in eastern North America and eastern Asia. Several species are known by the common name scaly polypody and resurrection fern.
Hymenophyllum is a genus of ferns in the family Hymenophyllaceae. Its name means "membranous leaf", referring to the very thin translucent tissue of the fronds, which gives rise to the common name filmy fern for this and other thin-leaved ferns. The leaves are generally only one cell thick and lack stomata, making them vulnerable to desiccation. Consequently, they are found only in very humid areas, such as in moist forests and among sheltered rocks. They are small and easy to overlook.
Pecluma is a genus of ferns in the family Polypodiaceae, subfamily Polypodioideae, according to the Pteridophyte Phylogeny Group classification of 2016 (PPG I). They are called rockcap ferns.
Tectaria is a genus of fern in the family Tectariaceae, according to the Pteridophyte Phylogeny Group classification of 2016. Halberd fern is a common name for species in this genus.
Lomariopsis is the type genus of the fern family Lomariopsidaceae.
Doodia is a genus of ferns in the family Blechnaceae, subfamily Blechnoideae, in the suborder Aspleniineae. It is named after Samuel Doody (1656-1706), an English botanist. Distribution of the genus includes parts of Australia and New Zealand.
Austroblechnum is a genus of ferns in the family Blechnaceae, subfamily Blechnoideae, according to the Pteridophyte Phylogeny Group classification of 2016. The genus is accepted in a 2016 classification of the family Blechnaceae, but other sources sink it into a very broadly defined Blechnum, equivalent to the whole of the PPG I subfamily.
Cranfillia is a genus of ferns in the family Blechnaceae, subfamily Blechnoideae, according to the Pteridophyte Phylogeny Group classification of 2016. The genus is accepted in a 2016 classification of the family Blechnaceae, but other sources sink it into a very broadly defined Blechnum, equivalent to the whole of the PPG I subfamily.
Lomaridium is a genus of ferns in the family Blechnaceae, subfamily Blechnoideae, according to the Pteridophyte Phylogeny Group classification of 2016. The genus is accepted in a 2016 classification of the family Blechnaceae, but other sources sink it into a very broadly defined Blechnum, equivalent to the whole of the PPG I subfamily.
Lomariocycas is a genus of ferns in the family Blechnaceae, subfamily Blechnoideae, according to the Pteridophyte Phylogeny Group classification of 2016. The genus is accepted in a 2016 classification of the family Blechnaceae, but other sources sink it into a very broadly defined Blechnum, equivalent to the whole of the PPG I subfamily.
Parablechnum is a genus of ferns in the family Blechnaceae, subfamily Blechnoideae, according to the Pteridophyte Phylogeny Group classification of 2016. The genus is accepted in a 2016 classification of the family Blechnaceae, but other sources sink it into a very broadly defined Blechnum, equivalent to the whole of the PPG I subfamily.
Amauropelta is a genus of ferns in the family Thelypteridaceae, subfamily Thelypteridoideae, in the Pteridophyte Phylogeny Group classification of 2016. Other sources sink the genus into a very broadly defined genus Thelypteris.
Megalastrum is a genus of ferns in the family Dryopteridaceae, subfamily Elaphoglossoideae, in the Pteridophyte Phylogeny Group classification of 2016. The genus has around 100 species, mainly found in tropical America and Africa.
Serpocaulon is a genus of ferns in the family Polypodiaceae, subfamily Polypodioideae, according to the Pteridophyte Phylogeny Group classification of 2016 (PPG I). The genus is native to Northern and Southern America.