''Polygonum dentoceras'' (

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 myriophylla'') is a rare species of flowering plant in the knotweed family known by the common names sandlace, woody wireweed, and Small's jointweed. It is

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 ...

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

in the United States, where it is limited to the central ridges of the peninsula, including the

Lake Wales Ridge The Lake Wales Ridge, sometimes referred to as the Mid-Florida Ridge,Eastern States Archaeological Federation. ''Archaeology of Eastern North America, Volume 11'', p. 54 is a sand ridge running for about 150 miles south to north in Central Florida. ...

. It is threatened by the loss and degradation of its habitat. It is a federally listed

endangered species An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inv ...

of the United States.

Description

This plant is a mat-forming sub

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

which spreads along the ground and grows up to 2 meters long. The sprawling branches have shreddy bark. The leaves are needle-like and under a centimeter long. The small

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 ...

contains white, pink or yellow flowers each 1 or 2 millimeters long.''Polygonella myriophylla''.
Flora of North America. The plant reproduces sexually via its seeds and

vegetatively Vegetative reproduction (also known as vegetative propagation, vegetative multiplication or cloning) is any form of asexual reproduction occurring in plants in which a new plant grows from a fragment or cutting of the parent plant or spec ...

by cloning.USFWS
''Polygonella myriophylla''.
August 2010. It engages in

allelopathy Allelopathy is a biological phenomenon by which an organism produces one or more biochemicals that influence the germination, growth, survival, and reproduction of other organisms. These biochemicals are known as allelochemicals and can have be ...

, the release of chemicals including

gallic acid Gallic acid (also known as 3,4,5-trihydroxybenzoic acid) is a trihydroxybenzoic acid with the formula C6 H2( OH)3CO2H. It is classified as a phenolic acid. It is found in gallnuts, sumac, witch hazel, tea leaves, oak bark, and other plants. It i ...

and

hydroquinone Hydroquinone, also known as benzene-1,4-diol or quinol, is an aromatic organic compound that is a type of phenol, a derivative of benzene, having the chemical formula C6H4(OH)2. It has two hydroxyl groups bonded to a benzene ring in a ''para'' ...

, to prevent other plants from growing directly next to it.Weidenheimer, J. D. and J. T. Romeo. (2004)
Allelochemicals of ''Polygonella myriophylla'': Chemistry and soil degradation.
30(5) 1067.

Taxonomy

The species was first described in 1924 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 ...

as ''Dentoceras myriophylla''. It was later transferred to the genus ''Polygonella''. 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, the genus ''Polygonella'' 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 myriophylla''" was unavailable, 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 dentoceras'' was published in 2011.

Ecology and conservation

Visitors to the flowers include the bee '' Dialectus placidensis'', the shore fly '' Allotrichoma abdominalis'', and the hairstreak butterfly '' Hemiargus ceraunus''. This plant is a member of the

Florida scrub Florida sand pine scrub is an endangered subtropical forest ecoregion found throughout Florida in the United States. It is found on coastal and inland sand ridges and is characterized by an evergreen xeromorphic plant community dominated by shrub ...

plant community. It occurs in dry white-sand scrub dominated by Florida rosemary, as well as oak scrub,

flatwoods Flatwoods, pineywoods, pine savannas and longleaf pine-wiregrass ecosystem are terms that refer to an ecological community in the southeastern coastal plain of North America. Flatwoods are an ecosystem maintained by wildfire or prescribed fire an ...

, roadsides, and occasionally

sandhill A sandhill is a type of ecological community or xeric wildfire-maintained ecosystem. It is not the same as a sand dune. It features very short fire return intervals, one to five years. Without fire, sandhills undergo ecological succession and be ...

s. Threats to this species include the destruction of its habitat during the conversion to residential and agricultural property, particularly

citrus ''Citrus'' is a genus of flowering plant, flowering trees and shrubs in the rue family, Rutaceae. Plants in the genus produce citrus fruits, including important crops such as Orange (fruit), oranges, Lemon, lemons, grapefruits, pomelos, and lim ...

groves.''Polygonella myriophylla''.
The Nature Conservancy.

Fire suppression Wildfire suppression is a range of firefighting tactics used to suppress wildfires. Firefighting efforts in wild land areas require different techniques, equipment, and training from the more familiar structure fire fighting found in populated a ...

may have a negative effect on this plant, because it is adapted to a habitat that depends on

wildfire A wildfire, forest fire, bushfire, wildland fire or rural fire is an unplanned, uncontrolled and unpredictable fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire ...

. As of 2010 there were 140 occurrences. It is difficult to count or estimate the number of individuals, because what may appear to be many separate individuals may be the clones of one plant.

References

{{Taxonbar, from1=Q42710309, from2=Q7226452 dentoceras Endemic flora of Florida