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Gymnosphaera
''Gymnosphaera'' is a genus of tree ferns in family Cyatheaceae. Taxonomy The genus was originally described by Carl Ludwig Blume in 1828. It was frequently treated by later authors as a synonym of ''Cyathea'' or '' Alsophila''. In the Pteridophyte Phylogeny Group The Pteridophyte Phylogeny Group (PPG) is an informal international group of systematic botanists who collaborate to establish on the classification of pteridophytes ( lycophytes and ferns) that reflects knowledge about plant relationships discove ... classification of 2016 (PPG I), ''Gymnosphaera'' was left as a synonym of ''Alsophila'', as evidence to support its reliable separation was lacking. More recently, Shi-Yong Dong and collaborators proposed the revival and recircumscription of the genus based on additional phylogenetic evidence, an act subsequently accepted by other tree fern workers. Phylogeny , the following species are accepted in the genus as currently circumscribed by the Checklist of Ferns and Lycop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alsophila (plant)
''Alsophila'' is a genus of tree ferns in the family Cyatheaceae. It has also been considered to be a section in the subgenus '' Cyathea'' of the genus ''Cyathea''. Description Species of ''Alsophila'' have a treelike growth habit, with an erect trunk that rarely branches, or sometimes a more shrublike habit, with a creeping stem. Their fronds are large, with a strawlike stalk (stipe), dark brown or black in colour. Brown or dark brown scales are present, with distinct margins. The blade (lamina) of the frond is divided one to three times (one- to three-pinnate). The sori (spore-producing structures) are rounded and borne on smaller veins on the lower surface of the frond. An indusium (a covering to the sori) may or may not be present; if present initially, it may be lost as the frond ages. ''Alsophila'' is now separated from the other genera in the family Cyatheaceae primarily on the basis of molecular phylogenetic studies. The scales on the stalks (petioles) provide a mor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gymnosphaera Capensis
''Gymnosphaera capensis'', synonyms ''Alsophila capensis'' and ''Cyathea capensis'', (known as the "forest tree fern") is a regionally widespread and highly variable species of tree fern. It is indigenous to Southern Africa (subsp. ''capensis'') and South America (subsp. ''polypodioides''). Description Both subspecies of ''Gymnosphaera capensis'' have a slender, erect trunk that is up to tall (occasionally even ) and about 15 cm in diameter. The fronds are tripinnate, born on long stipes (stalks), and 2–3 m in length. The main stem of the leaf (rachis) is smooth to slightly warty and covered in scales that range from tan to brown or dark brown. The frond stalks are covered with dark brown or black scales. The smallest leaflets (pinnae) have toothed (serrated) margins. The lowest pinnae may be separated from the others along the rachis and form a clump around the crown, similar to the "wig" of ''Gymnosphaera baileyana''. This moss-like tuft of tiny, reduced leav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gymnosphaera Glabra
''Gymnosphaera glabra'', synonyms ''Alsophila glabra'' and ''Cyathea glabra'', is a species of tree fern native to Borneo, western Java, Sumatra, the Lesser Sunda Islands, Sulawesi, and the Malay Peninsula, where it grows in lowland swamp forest and montane forest at an elevation of up to 1500 m. The trunk of this plant is erect and 2–4 m tall. Fronds are bi- or tripinnate and 1–2 m in length. Characteristically of this species, the lowest pinnae may be significantly reduced. The stipe is very dark and bears basal scales. These scales are dark, glossy and have a paler margin and fragile edges. Sori are produced in groups of one to three on fertile pinnule veins. They lack indusia. Large and Braggins (2004) noted that ''G. glabra'' is very similar to '' Gymnosphaera gigantea'' and appears to form part of a complex that also includes '' G. podophylla'' and '' G. subdubia''. Further study is needed to determine the nature of the relationship between these taxa In biology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gymnosphaera Biformis
''Gymnosphaera biformis'', synonyms ''Alsophila biformis'' and ''Cyathea biformis'', is a species of tree fern native to New Guinea and the Maluku Islands, where it grows against trees in mossy forest and rain forest at elevations of 850–2200 m. The climbing trunk is very thin, only 1–2 cm in diameter, but can reach 3 m in height. The apex of the trunk is covered in scales. Two types of fronds are produced, simple pinnate fronds, which are sterile, and bipinnate fronds, which may be fertile. The stipe is smooth, glossy and very dark, almost to the point of being black. It is covered at the base with long, very dark scales that have a pale margin. Fertile pinnules are distinctly stalked and lobed. Sori occur in four pairs per pinnule lobe and lack indusia. ''Gymnosphaera biformis'' is a very unusual species, being a climbing or scrambling fern with a very thin trunk. Plants often cling to supporting trees by their roots. The closest relative of this species appears t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
