|
Sphaeropteris Aciculosa
''Sphaeropteris'' is a genus of Cyatheales, tree fern in the family Cyatheaceae. It has been treated as a subgenus within the genus ''Cyathea'', but is accepted in the Pteridophyte Phylogeny Group classification of 2016 (PPG I). Description Species of ''Sphaeropteris'' have a treelike habit, usually with a single tall stem, and large fronds to or more in length. The stalk (stipe) of the frond is strawlike or purple in colour, with pale to brown scales. The Sorus, sori (spore-bearing structures) are rounded, with or without Indusium, indusia (covers). ''Sphaeropteris'' is now separated from the other genera in the family Cyatheaceae primarily on the basis of Molecular phylogenetics, molecular phylogenetic studies. However, the scales on the stalks (petioles) provide a morphological distinction. ''Sphaeropteris'' has scales without distinct margins, whereas the other genera have scales with distinct margins. Taxonomy The genus ''Sphaeropteris'' was erected by Johann Jakob Bern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyathea RGBS
''Cyathea'' is a genus of tree ferns, the type genus of the fern order Cyatheales. The genus name ''Cyathea'' is derived from the Greek ''kyatheion'', meaning "little cup", and refers to the cup-shaped sori on the underside of the fronds. Description The species of ''Cyathea'' are mostly terrestrial ferns, usually with a single tall stem. Rarely, the trunk may be branched or creeping. Many species also develop a fibrous mass of roots at the base of the trunk. The genus has a pantropical distribution, with over 470 species. They grow in habitats ranging from tropical rain forests to temperate woodlands. Classification Conant ''et al.'' in 1996, concluded on molecular cpDNA and morphological evidence that a system of three clades – ''Alsophila'', ''Cyathea'' and ''Sphaeropteris'' was the most accurate reflection of evolutionary lineages within the Cyatheaceae, ''Alsophila'' being the most basal and ''Cyathea'' and ''Sphaeropteris'' derived sister groups. In the Pteridophyte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
