Atraphaxis is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

s in the family

Polygonaceae The Polygonaceae are a family of flowering plants known informally as the knotweed family or smartweed—buckwheat family in the United States. The name is based on the genus ''Polygonum'', and was first used by Antoine Laurent de Jussieu in 1789 ...

with about 40

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

Description

Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and bear the leaves and flowers. The leaves are simple and alternate, with very short stalks (almost sessile). The

ochrea An ochrea (Latin ''ocrea'', greave or protective legging), also spelled ocrea, is a plant structure formed of stipules fused into a sheath surrounding the stem, and is typically found in the Polygonaceae The Polygonaceae are a family of flower ...

s are membranous and usually two-veined, more-or-less joined at the base. 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 several bundles ( fascicles) of one to three flowers. The flowers have persistent

tepal A tepal is one of the outer parts of a flower (collectively the perianth). The term is used when these parts cannot easily be classified as either sepals or petals. This may be because the parts of the perianth are undifferentiated (i.e. of very ...

s, either arranged in a narrow tube with unequal lobes or bell-shaped with equal segments. The fruits are wingless

achene 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 ...

Taxonomy

The genus ''Atraphaxis'' was erected by

Carl Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...

in 1753. As with many other genera in the family Polygonaceae, the boundaries between the genera have been unclear, and some or all species placed in other genera.

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 have shown that ''Atraphaxis'' forms a distinct clade. The genus is placed in the tribe Polygoneae of the subfamily

Polygonoideae Polygonoideae is a subfamily of plants in the family Polygonaceae. It includes a number of plants that can be highly invasive, such as Japanese knotweed, ''Reynoutria japonica'', and its hybrid with '' R. sachalinensis'', ''R.'' × ''bohemica'' ...

. Within the tribe, it is most closely related to the genera ''

Duma A duma (russian: дума) is a Russian assembly with advisory or legislative functions. The term ''boyar duma'' is used to refer to advisory councils in Russia from the 10th to 17th centuries. Starting in the 18th century, city dumas were for ...

'' and ''

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 ...

'', forming the so-called "DAP clade".

Species

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 ...

accepted 41 species: *'' Atraphaxis angustifolia'' Jaub. & Spach *''

Atraphaxis ariana Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' (Grigorj.) T.M.Schust. & Reveal *'' Atraphaxis arida'' (Boiss. & Hausskn.) S.Tavakkoli & Kaz.Osaloo *'' Atraphaxis atraphaxiformis'' (Botsch.) T.M.Schust. & Reveal *''

Atraphaxis aucheri Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' Jaub. & Spach *''

Atraphaxis avenia Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' Botsch. *''

Atraphaxis badghysi Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' Kult. *''

Atraphaxis billardierei Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' Jaub. & Spach *''

Atraphaxis binaludensis Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' S.Tavakkoli, Mozaff. & Kaz.Osaloo *''

Atraphaxis botuliformis Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' (Mozaff.) S.Tavakkoli & Mozaff. *''

Atraphaxis bracteata Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' Losinsk. *''

Atraphaxis canescens Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' Bunge *''

Atraphaxis caucasica Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' (Hoffm.) Pavlov *''

Atraphaxis compacta Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' Ledeb. *'' Atraphaxis daghestanica'' (Lovelius) Lovelius *'' Atraphaxis decipiens'' Jaub. & Spach *''

Atraphaxis dumosa Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' (Boiss.) S.Tavakkoli & Kaz.Osaloo *'' Atraphaxis frutescens'' (L.) K.Koch *'' Atraphaxis grandiflora'' Willd. *''

Atraphaxis intricata Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' Mozaff. *''

Atraphaxis irtyschensis Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' Chang Y.Yang & Y.L.Han *'' Atraphaxis kamelinii'' Yurtseva *'' Atraphaxis karataviensis'' Pavlov & Lipsch. *'' Atraphaxis kermanica'' S.Tavakkoli & Kaz.Osaloo *''

Atraphaxis khajeh-jamali Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' (Khosravi & Poormahdi) S.Tavakkoli & Kaz.Osaloo *'' Atraphaxis kopetdagensis'' Kovalevsk. *'' Atraphaxis laetevirens'' (Ledeb.) Jaub. & Spach *'' Atraphaxis macrocarpa'' Rech.f. & Schiman-Czeika *''

Atraphaxis manshurica Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' Kitag. *'' Atraphaxis muschketowii'' Krasn. *'' Atraphaxis popovii'' (Borodina) Yurtseva *'' Atraphaxis pungens'' (M.Bieb.) Jaub. & Spach *''

Atraphaxis pyrifolia Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' Bunge *'' Atraphaxis radkanensis'' S.Tavakkoli, Kaz.Osaloo & Mozaff. *'' Atraphaxis rodinii'' Botsch. *''

Atraphaxis salicornioides Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' (Jaub. & Spach) S.Tavakkoli & Kaz.Osaloo *'' Atraphaxis seravschanica'' Pavlov *''

Atraphaxis spinosa Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' L. *''

Atraphaxis suaedifolia Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' Jaub. & Spach *''

Atraphaxis teretifolia Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' (Popov) Kom. *''

Atraphaxis toktogulica Atraphaxis is a genus of flowering plants in the family Polygonaceae with about 40 species. Description Species of ''Atraphaxis'' are much branched woody plants, forming shrubs or shrubby tufts. The current year's branchlets are herbaceous and b ...

'' (Lazkov) T.M.Schust. & Reveal

References

{{Taxonbar, from=Q889292 Polygonoideae Polygonaceae genera