''Polygonum delopyrum'' (

synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are all ...

''Polygonella ciliata''), the fringed jointweed or hairy jointweed, is a plant species

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to Florida. It is found in pinelands and sandy

pine barrens Pine barrens, pine plains, sand plains, or pineland areas occur throughout the U.S. from Florida to Maine (see Atlantic coastal pine barrens) as well as the Midwest, West, and Canada and parts of Eurasia. Perhaps the most well known pine-barre ...

at elevations less than 50 m, in central and southern parts of the state. ''Polygonum delopyrum'' is an annual herb up to 110 cm tall, branching above the base. Leaves are narrow and linear, up to 5 cm long, with

cilia The cilium, plural cilia (), is a membrane-bound organelle found on most types of eukaryotic cell, and certain microorganisms known as ciliates. Cilia are absent in bacteria and archaea. The cilium has the shape of a slender threadlike projecti ...

(long flexible hairs) along the margins.

Inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

is up to 45 mm long. Flowers are white, some

hermaphroditic In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many taxonomic groups of animals (mostly invertebrates) do not have separ ...

(male and female together) but others

pistillate Gynoecium (; ) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more) ''pistils'' ...

(female only).

Achenes An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and indehiscent (they do not ope ...

are brown, triangular in cross-section, up to 4 mm long.

Taxonomy

The species was first described in 1856 by

Carl Meissner Carl Daniel Friedrich Meissner (1 November 1800 – 2 May 1874) was a Swiss botanist. Biography Born in Bern, Switzerland on 1 November 1800, he was christened Meisner but later changed the spelling of his name to Meissner. For most of his 40 ...

as ''Polygonella ciliata''. It was later placed in the genus ''Polygonella'' (under the name ''Polygonella ciliata'') by

John Kunkel Small John Kunkel Small (January 31, 1869 – January 20, 1938) was an American botanist. Born on January 31, 1869, in Harrisburg Pennsylvania, Kunkel studied botany at Franklin & Marshall College and Columbia University. He was the first Curator of ...

, but in 2015, following a series of

molecular phylogenetic Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

studies, this genus was subsumed into ''

Polygonum ''Polygonum'' is a genus of about 130 species of flowering plant in the buckwheat and knotweed family Polygonaceae. Common names include knotweed and knotgrass (though the common names may refer more broadly to plants from Polygonaceae). In the ...

''. However, the name "''Polygonum ciliata''" had already been used, so the

replacement name In biological nomenclature, a ''nomen novum'' (Latin for "new name"), new replacement name (or replacement name, new substitute name, substitute name) is a scientific name that is created specifically to replace another scientific name, but only w ...

''Polygonum delopyrum'' was published. ''

Polygonum basiramia ''Polygonum basiramia'' (Synonym (taxonomy), synonym ''Polygonella basiramia'') is a rare species of flowering plant in the Polygonaceae, knotweed family known by the common names wireweed, hairy wireweed, purple wireweed, and Florida jointweed. ...

'' has been treated as a variety of ''P. delopyrum'' (under the name ''Polygonella ciliata'' var. ''basiramia'') by some authors,Horton, James Heathman. 1963. Brittonia 15(3): 195. but is classed as a separate species by the

Flora of North America The ''Flora of North America North of Mexico'' (usually referred to as ''FNA'') is a multivolume work describing the native plants and naturalized plants of North America, including the United States, Canada, St. Pierre and Miquelon, and Greenla ...

Plants of the World Online Plants of the World Online (POWO) is an online database published by the Royal Botanic Gardens, Kew. It was launched in March 2017 with the ultimate aim being "to enable users to access information on all the world's known seed-bearing plants by ...

and other recent publications. It is very similar but branches mostly at or below ground level.

References

{{Taxonbar, from1=Q42710302, from2=Q16988314 delopyrum Endemic flora of Florida Plants described in 1856 Flora without expected TNC conservation status