Myriocarpa
Encyclopedia
Myriocarpa is a genus
woody plant which ranges in size from shrubs to small trees and is endemic to Central
and South America
. Within the Urticaceae
, Myriocarpa is characterized by long pendulous string-like female inflorescences of apparently naked flowers and stems which release a watery latex
when cut. Estimates for the diversity of the genus range from five to eighteen species
. Research for Flora Mesoamericana indicates that there are probably fifteen to twenty species.
The genus was described by George Bentham
in 1846 based on Colombian specimens of Myriocarpa stipitata collected by Mss. Barclay. Weddell placed Myriocarpa in the Urticaceae
tribe Boehmerieae despite its anomalous pubescence, cystolith
morphology
and wood anatomy. In his review of the Urticaceae, Friis retained its position within the Boehmerieae, presumably because its position in any other Urticaceae tribe would be equally ambiguous. The position of Myriocarpa within the Boehmerieae is not supported by recent phylogenetic analyses of trnL-F sequence data that recovered Myriocarpa within a strongly supported clade
including both the Urticeae and Lecantheae tribes.
Its position within either one of these tribes however, is unresolved. Based on hair, leaf and flower morphology, Myriocarpa could equally well be placed in the Lecantheae (absence of hooked hairs) or the Urticeae (alternate leaves, pistillodes not ejecting the achene
) and further research, both molecular and morphological, is warranted.
The last major revision of the genus, at which time six species were recognized, was that of Hugh Algernon Weddell
. Since this revision Myriocarpa has attracted little taxonomic interest outside of floristic treatments, despite its unusual female inflorescence morphology and ambiguous position within the Urticaceae and currently a total of 24 species names have been published.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
woody plant which ranges in size from shrubs to small trees and is endemic to Central
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
and South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
. Within the Urticaceae
Urticaceae
Urticaceae, or the nettle family, is a family of flowering plants. The family name comes from the genus Urtica . Urticaceae includes a number of well-known and useful plants, including the aforementioned nettles, Ramie , māmaki , and ajlai .The family includes approximately 2600 species, grouped...
, Myriocarpa is characterized by long pendulous string-like female inflorescences of apparently naked flowers and stems which release a watery latex
Latex
Latex is the stable dispersion of polymer microparticles in an aqueous medium. Latexes may be natural or synthetic.Latex as found in nature is a milky fluid found in 10% of all flowering plants . It is a complex emulsion consisting of proteins, alkaloids, starches, sugars, oils, tannins, resins,...
when cut. Estimates for the diversity of the genus range from five to eighteen species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
. Research for Flora Mesoamericana indicates that there are probably fifteen to twenty species.
The genus was described by George Bentham
George Bentham
George Bentham CMG FRS was an English botanist, characterized by Duane Isely as "the premier systematic botanist of the nineteenth century".- Formative years :...
in 1846 based on Colombian specimens of Myriocarpa stipitata collected by Mss. Barclay. Weddell placed Myriocarpa in the Urticaceae
Urticaceae
Urticaceae, or the nettle family, is a family of flowering plants. The family name comes from the genus Urtica . Urticaceae includes a number of well-known and useful plants, including the aforementioned nettles, Ramie , māmaki , and ajlai .The family includes approximately 2600 species, grouped...
tribe Boehmerieae despite its anomalous pubescence, cystolith
Cystolith
Cystolith is a botanical term for the inorganic concretions, usually of calcium carbonate, formed in a cellulose matrix in special cells, generally in the leaf of plants of certain families, e.g. Ficus elastica, the Indian rubber plant of the family Moraceae...
morphology
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
and wood anatomy. In his review of the Urticaceae, Friis retained its position within the Boehmerieae, presumably because its position in any other Urticaceae tribe would be equally ambiguous. The position of Myriocarpa within the Boehmerieae is not supported by recent phylogenetic analyses of trnL-F sequence data that recovered Myriocarpa within a strongly supported clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
including both the Urticeae and Lecantheae tribes.
Its position within either one of these tribes however, is unresolved. Based on hair, leaf and flower morphology, Myriocarpa could equally well be placed in the Lecantheae (absence of hooked hairs) or the Urticeae (alternate leaves, pistillodes not ejecting the achene
Achene
An achene is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate and indehiscent...
) and further research, both molecular and morphological, is warranted.
The last major revision of the genus, at which time six species were recognized, was that of Hugh Algernon Weddell
Hugh Algernon Weddell
Hugh Algernon Weddell was a physician and botanist, specialising in South American flora.Weddell was born at Birches House, Painswick near Gloucester, England but was raised in France and educated at the Lycée Henri IV, where he received a medical degree in 1841...
. Since this revision Myriocarpa has attracted little taxonomic interest outside of floristic treatments, despite its unusual female inflorescence morphology and ambiguous position within the Urticaceae and currently a total of 24 species names have been published.