Biotic Interactions (GloBI) · NCBI – National Center for Biotechnology Information. Alsophila firma. Open Interactive Map. Alsophila firma image. Click to Display. Brief summary. No one has contributed a brief summary to this page yet. Explore what EOL knows about Alsophila firma. Add a brief summary to this page. Alsophila firma (Baker) D.S. Conant is an accepted name. This name is the accepted name of a species in the genus Alsophila (family Cyatheaceae). The record.
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Commonly known as the scaly tree ferns, Cyatheaceae are a clade of ca. Psilopsida; Equisetopsida; Marattiopsida; Polypodiopsida, which include 11 orders, and 37 families with ca. Cyatheaceae are placed within the class of ferns known as Polypodiopsida or the Leptosporangiate Ferns which contains the xlsophila majority of fern diversity. In Leptosporangiate Ferns the sporangia develop from a single daughter epidermal cell and the mature sporangial walls are only one cell thick.
Conversely, in the eusporangiate ferns Psilopsida, Equisetopsida and Marattiaceaeas well as the epidermal daughter cell, a group of adjacent cells become involved in the formation of the sporangium Sporne, It is thought that these lineages began to diverge around mya — mya. The Polypodiales, which are an incredibly diverse group, are thought to be the sister clade to Cyatheales Pryer et al. The arborescent rhizome aksophila Cyathea medullaris.
Approx 10 m tall. Image attributed to Chris Reilly. Many of the species within Cyatheales have arborescent trunk-like stems, but other members of the order have a creeping and non-arborescent form. Tree ferns exhibit a range of morphological variations and sizes: Furthermore, the arborescent growth form seen in tree ferns is not unique — it can also be seen in Blechnaceae Korall et al. There are two morphological synapomorphies which can assist in identifying a tree fern.
However, the presence of pneumathodes may unite the clade, but it is also found in other leptopsporangiate ferns, and may represent the ancestral plesiomorphic condition of this group.
Radial symmetry alsophilw the shoots is a common feature of most tree ferns, fifma, the character does not have a common origin within the clade homoplasticwith reversals to firmq shoots seen ffirma Loxomataceae and Metaxyaceae Korall et al. The arborescent tree-like Alsophila firma. It is estimated there are ca. However, new species continue to be described, with three new species of Cyathea being discovered in the Northern Andes only very recently Lehnert, The dictyostele vasculature of Alsophila firma.
With the exception of eight species of HymenophyllopsisCyatheaceae are made up exclusively of arborescent tree-like plants which includes the tallest living ferns, whose erect trunk-like rhizomes can reach over 20 m tall Lehnert, Cyatheaceae usually have large leaves to 5 m that are pinnate, and have vasculature made up of dictyosteles Smith et al.
The genera Dicksonia ca. Dicksoniaceae and Cibotium ca. However, they differ from Cyatheaceae by the presence of hairs instead of scales as indumentum Korall et al. A further key morphological distinction is the abaxial sori in Cyatheaceae, whereas in Cibotium and Dicksonia the sori are marginal or submarginal. Dicksonia sellowiana ; 1B: Hairs at the stipe base of D. Cyathea brownii ; 2B: Images above attributed to Chris Reilly.
Comparing the sori of Dicksoniaceae and Cyatheaceae. Abaxial scales of Sphaeropteris barbata Scales: Abaxial scales of Cyathea capensis Scales: Marginal scales of Dicksonia arborescens Scale: Worldwide distribution of Cyatheaceae based on data from Encyclopedia of Life www. Cyatheaceae has a pan-tropical southern temperate distribution. The extant scaly tree ferns are commonly found firmx the tropics, from the wet lowlands to mid elevations. However, some species are also found in high mountain areas in the tropics at elevations up to m Bystrikova, Madagascar is an example of this pronounced local endemism, the island has 49 endemic species of scaly tree ferns Janssen et al.
The diminutive Hymenophyllopsis superba. Species of the genus Hymenophyllopsis are small plants with pinnate fronds, mostly cm forma. Their tissue is only cells thick with chloroplasts present only lasophila epidermal cells and lacking in stomates.
SEINet Portal Network – Alsophila firma
The stems are usually short-creeping to sub-erect or erect. Hymenophyllopsis look superficially similar to filmy ferns Hymenophyllaceae because of the similar characteristics of the lamina.
However, this is likely to be the result of convergent evolution rather than a close taxonomic relationship. Image attributed to Intermountain Herbarium via intermountainbiota. The plants of the Roraima Formation Guayana Shield are subjected so some extreme climatic conditions: Along with the geographical isolation of the tepuis, it appears that the climatic conditions in the Roraima formation have facilitated the evolution of a group of plants with morphological adaptations very different to those normally associated to the scaly tree ferns.
The affinity of Hymenophyllopsis with Cyatheaceae had been suggested but has only been confirmed in recent years through phylogenetic studies Wolf et al. Recent studies suggest strongly that Hymenophyllopsis nests within Cyathea as they both share marginal scales without apical setae and cyatheoid cup-shaped indusia Korall et al.
More recently, Hymenophyllopsis has been described as a subgenus within Cyathea Christenhusz, Generic delimitations of Cyatheaceae have differed substantially across various studies and have been hotly debated in recent years. However, with evermore phylogenetic analyses and data botanists are beginning to piece together that main groups or genera within the family.
Cyatheaceae: The Scaly Tree Ferns
InTryon recognised six genera within Cyatheaceae: In a later study, Stein et al. AlsophilaCyathea and Sphaeropteris. This study moved Cnemidaria and Trichipteris which nested within Cyatheaand Nephelea now nested within Alsophila. Alsophila was reclassified to include ca. These proposed lineages are separated by differences in scale morphology. Images above are simplified interpretations of petiole scales for Cyatheaceae, Fig. Conform scale found in Sphaeropteris showing cells of equal size and orientation; 4B: Marginate Scales with Seta found in Alsophila s.
In the most recent phylogenetic study, Korall et al.
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Neoendemism in Madagascan scaly tree ferns results from recent, coincident diversification bursts. Evolution, Monophyletic groups and their relationships alspohila revealed by four protein-coding plastic loci.
A molecular phylogeny of scaly tree ferns Cyatheaceae. American Journal of Botany94, Three new species of scaly tree ferns Cyathea-Cyatheaceae from the northern Andes.
Phylogeny and figma of ferns Monilophytes with a focus on the early leptosporangiate divergences. American Journal of Botany91, Conservation priorities for tree ferns Cyatheaceae in Sri Lanka.
Taiwania, Fern Phylogeny inferred from leptosporangiate species and three plastid genes. Taxon, A classification for extant ferns. The implications of chloroplast DNA restriction site variation on the classification and phylogeny of the Cyatheaceae. The classification alsolhila the Cyatheaceae. Gray Herb Phylogenetic relationships of the enigmatic fern families Hymenophyllopsidaceae and Lophosoriaceae: Permission granted to reproduce for personal and educational use only.
Commercial copying, hiring and lending is prohibited. A Scaly Tree Fern: The radial shoot symmetry of a tree fern. About Chris Reilly I am a botanist who is particularly interested in the vascular and lower plants of the British Isles.
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