Arachis

Arachis is a genus of about 70 species of annual and perennial flowering plants in the family, native to South America, and was recently assigned to the informal monophyletic Pterocarpus clade of the Dalbergieae. At least one species, the peanut, is a major food crop species of global importance; some of the other species are cultivated for food to a small extent in South America. Other species such as A. pintoi are cultivated worldwide as forage and soil conditioner plants, with the leaves providing high-protein feed for grazing livestock and a nitrogen source in agroforestry and permaculture systems.
Arachis species, including the peanut, are used as food plants by some Lepidoptera species, including the flame shoulder, nutmeg, and turnip moth.

Species

Arachis comprises the following sections and species:

Section ''Arachis''

Arachis batizocoi Krapov. & W.C. Greg.Arachis benensis Krapov. et al.Arachis cardenasii Krapov. & W.C. Greg.Arachis correntina Krapov. & W.C. Greg.Arachis cruziana Krapov. et al.Arachis decora Krapov. et al.Arachis diogoi HoehneArachis duranensis Krapov. & W.C. Greg.Arachis glandulifera StalkerArachis gregoryi C. E. Simpson et al.Arachis helodes Carl Friedrich [Philipp von Martius|Mart.] ex Krapov. & RigoniArachis herzogii Krapov. et al.Arachis hoehnei Krapov. & W.C. Greg.Arachis hypogaea L.—peanut

* subsp. fastigiata Waldron
** var. aequatoriana Krapov. & W. C. Greg
** var. fastigiata Krapov. & W. C. Greg
** var. peruviana Krapov. & W. C. Greg
** var. vulgaris Harz
* subsp. hypogaea L.
** var. hirsuta J. Kohler
** var. hypogaea L.Arachis ipaensis Krapov. & W.C. Greg.Arachis kempff-mercadoi Krapov. et al.Arachis krapovickasii C. E. Simpson et al.Arachis kuhlmannii Krapov. & W.C. Greg.Arachis linearifolia Valls et al.Arachis magna Krapov. et al.Arachis microsperma Krapov. et al.Arachis monticola Krapov. & RigoniArachis palustris Krapov. et al.Arachis praecox Krapov. et al.Arachis schininii Krapov. et al.Arachis simpsonii Krapov. & W.C. Greg.Arachis stenosperma Krapov. & W.C. Greg.Arachis trinitensis Krapov. & W.C. Greg.Arachis valida Krapov. & W.C. Greg.Arachis villosa Benth.Arachis williamsii Krapov. & W.C. Greg.

Section ''Caulorrhizae''

Arachis pintoi Krapov. & W.C. Greg.Arachis repens Handro

Section ''Erectoides''

Arachis archeri Krapov. & W.C. Greg.Arachis benthamii HandroArachis brevipetiolata Krapov. & W.C. Greg.Arachis cryptopotamica Krapov. & W.C. Greg.Arachis douradiana Krapov. & W.C. Greg.Arachis gracilis Krapov. & W.C. Greg.Arachis hatschbachii Krapov. & W.C. Greg.Arachis hermannii Krapov. & W.C. Greg.Arachis major Krapov. & W.C. Greg.Arachis martii HandroArachis oteroi Krapov. & W.C. Greg.Arachis paraguariensis Chodat & Hassl.

* subsp. capibarensis Krapov. & W. C. Greg
* subsp. paraguariensis Chodat & Hassl.Arachis porphyrocalyx Valls & C. E. SimpsonArachis stenophylla Krapov. & W.C. Greg.

Section ''Extranervosae''

Arachis burchellii Krapov. & W.C. Greg.Arachis lutescens Krapov. & RigoniArachis macedoi Krapov. & W.C. Greg.Arachis marginata GardnerArachis pietrarellii Krapov. & W.C. Greg.Arachis prostrata Benth.—grassnutArachis retusa Krapov. et al.Arachis setinervosa Krapov. & W.C. Greg.Arachis submarginata Valls et al.Arachis villosulicarpa Hoehne

Section ''Heteranthae''

Arachis dardani Krapov. & W.C. Greg.Arachis giacomettii Krapov. et al.Arachis interrupta Valls & C. E. SimpsonArachis pusilla Benth.Arachis seridoensis Valls et al.Arachis sylvestris A. Chev.

Section ''Procumbentes''

Arachis appressipila Krapov. & W. C. Greg.Arachis chiquitana Krapov. et al.Arachis kretschmeri Krapov. & W.C. Greg.Arachis hassleri Krapov. et al.Arachis lignosa Krapov. & W.C. Greg.Arachis matiensis Krapov. et al.Arachis pflugeae C. E. Simpson et al.Arachis rigonii Krapov. & W.C. Greg.Arachis subcoriacea Krapov. & W.C. Greg.Arachis vallsii Krapov. & W.C. Greg.

Section ''Rhizomatosae''

Arachis nitida Valls et al.

Series ''Prorhizomatosae''

Arachis burkartii Handro

Series ''Rhizomatosae''

Arachis glabrata Benth.

* var. glabrata Benth.
* var. hagenbeckii F. J. Herm.Arachis pseudovillosa Krapov. & W.C. Greg.

Section ''Trierectoides''

Arachis guaranitica Robert [Hippolyte Chodat|Chodat] & Hassl.Arachis tuberosa Benth.

Section ''Triseminatae''

Arachis triseminata Krapov. & W.C. Greg.

Hybrids

Arachis × batizogaea Krapov. & A. Fernández