''Polygonum smallianum'' (

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 macrophylla'') is a species of flowering plant in the knotweed family known by the common name largeleaf jointweed. It is native to a small area around the border between

Alabama (We dare defend our rights) , anthem = "Alabama (state song), Alabama" , image_map = Alabama in United States.svg , seat = Montgomery, Alabama, Montgomery , LargestCity = Huntsville, Alabama, Huntsville , LargestCounty = Baldwin County, Al ...

and

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.

Description

This plant is a perennial herb or subshrub with stiff, erect stems coming from a woody base and taproot. It may exceed one meter in height. The leathery leaves are alternately arranged. The largest near the stem bases are up to 6.8 centimeters long. They are mostly oval with smooth edges and rounded tips. The

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 made up of a number of

raceme A raceme ( or ) or racemoid is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the s ...

s of flowers. There is a white- or pinkish-flowered form and a red-flowered form.

Taxonomy

The species was first described in 1856 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 ''Polygonella macrophylla''. 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 macrophylla''" 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 smallianum'' was published in 2011.

Distribution, habitat and conservation

This species occurs in the Florida scrub of the

Florida Panhandle The Florida Panhandle (also West Florida and Northwest Florida) is the northwestern part of the U.S. state of Florida; it is a Salient (geography), salient roughly long and wide, lying between Alabama on the north and the west, Georgia (U. ...

and a part of southern Alabama. It grows in open scrub and coastal

dune A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, f ...

s. Rare in general, it can be common in its range. The main threat to the species is the loss of its scrub habitat to development and silviculture.

References

{{Taxonbar, from=Q7226451 smallianum Flora of Alabama Flora of Florida Endemic flora of the United States Plants described in 1856