Dicksonia
Học thuậtThân thiện
Definition
- Noun:
- A genus of tree ferns native to temperate regions of Australasia, characterized by fronds that are bipinnatifid or tripinnatifid (divided into leaflets that are themselves divided) and typically having sori (clusters of spore-producing structures) located on the margins of the leaflets. In some taxonomic classifications, this genus is placed within the family Cyatheaceae.
Usage Examples
- Noun:
- The Dicksonia antarctica, a species within the genus Dicksonia, is a popular ornamental tree fern in gardens.
- Botanists study the fossil records of Dicksonia to understand the evolution of ferns.
Advanced Usage
- In Botanical Taxonomy: The placement of the genus Dicksonia has been debated, with some systems classifying it in the family Dicksoniaceae and others in Cyatheaceae.
- The reclassification of Dicksonia into the Cyatheaceae family was based on recent molecular studies.
Variants and Related Words
- Dicksoniaceae (n): The family name often associated with the genus .
- The family Dicksoniaceae includes several genera of tree ferns.
- Dicksonia antarctica (n): A specific, commonly cultivated species known as the soft tree fern or man fern.
- The Dicksonia antarctica can tolerate mild frosts.
Synonyms
- Tree fern: A general term for arborescent (tree-like) ferns, which includes species from the genus and others like .
- (Note: As a proper genus name, direct synonyms are not common. "Tree fern" is a descriptive, common-name synonym.)
Related Terms and Phrases
- Bipinnatifid: A botanical term describing a leaf division pattern where the primary leaflets are themselves deeply lobed or divided.
- Sori: The plural of , referring to the clusters of sporangia (spore cases) on the underside of fern fronds.
- Marginal sori: Sori that are located along the edges of the fern's leaflets or pinnae, a characteristic feature of many species.
Noun
- tree ferns of temperate Australasia having bipinnatifid or tripinnatifid fronds and usually marginal sori; in some classification systems placed in family Cyatheaceae