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Pediocactus

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Pediocactus
Pediocactus simpsonii
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Order: Caryophyllales
Family: Cactaceae
Subfamily: Cactoideae
Tribe: Cacteae
Genus: Pediocactus
Britton & Rose
Type species
 Pediocactus simpsonii 
Species

See text

Pediocactus (Greek: πεδίον (pedion) means "plain", "flat", "field") is a genus of cacti native to the Western United States. The genus comprises between 6 and 11 species, depending upon the authority. Species of this genus are referred to as hedgehog cacti, though that name is also applied to plants from the genera Echinocereus and Echinopsis.[1] Species may also be referred to as pincushion cacti, a common name which is also applied to other genera.

Description

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The Pediocactus genus includes small species of cactus that grow either individually or in clusters, reaching heights of up to 20 centimeters (7.9 in). The shoots, which can be green or glaucous, come in cylindrical, spherical, or depressed spherical shapes, with diameters ranging from 1 to 15 centimeters (0.39 to 5.91 in) and heights from 0.7 to 20 centimeters (0.28 to 7.87 in). Despite lacking ribs, these shoots have warts measuring 2 to 12 millimeters (0.079 to 0.472 in) in length and 2 to 11 millimeters (0.079 to 0.433 in) in diameter. The characteristic appearance is contributed to by the areoles, spaced 1 to 6 millimeters (0.039 to 0.236 in) apart (occasionally up to 12 millimeters (0.47 in)). The shoots also have thorns, varying in number, color, and orientation. There can be up to ten light gray or white central spines, measuring 0.5 to 3.2 centimeters (0.20 to 1.26 in), and three to 35 reddish to whitish marginal spines, which can be straight, curved, or comb-shaped, extending 0.1 to 2.1 centimeters (0.039 to 0.827 in) in length.[2]

The bell-shaped flowers at the top of the shoots come in colors ranging from yellow to magenta to white, with diameters of 1 to 2.5 centimeters (0.39 to 0.98 in). The flowers are characterized by a glabrous or nearly glabrous pericarpel and a short floral tube. Flowering typically occurs in spring, but certain species form buds in late autumn, with some capable of flowering even in their juvenile stages.[3]

The fruits, initially greenish and cylindrical to spherical, transform into reddish-brown, dry structures upon ripening. Opening with a vertical gap, the fruits may be bare or possess a few scales. As the fruit opens, the remaining flower partially detaches, leaving a residue resembling a cap. The fruits contain blackish-brown, wrinkled to tuberous, obovate, or pear-shaped seeds. These seeds ripen 4 to 6 weeks after flowering and remain viable for an exceptionally long period, lasting at least 10 years.[2]

Species

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As of December 2022, Plants of the World Online accepts the following species:

Image Scientific name Distribution
Pediocactus bradyi L.D.Benson Arizona
Pediocactus knowltonii L.D.Benson San Juan County, New Mexico
Pediocactus nigrispinus (Hochstätter) Hochstätter Idaho, Oregon, Washington
Pediocactus paradinei B.W.Benson Arizona
Pediocactus peeblesianus (Croizat) L.D.Benson Arizona
Pediocactus sileri (Daul) L.D.Benson southwestern Utah and northwestern Arizona
Pediocactus simpsonii (Engelm.) Britton & Rose Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, South Dakota, Utah, Wyoming

Synonyms

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The genus has 3 synonyms:

Sclerocactus and Pediocactus were also at one time reduced to synonymy, but this is not at present considered to be correct.

References

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  1. ^ "Echinopsis (Hedgehog Cacti)". Cactus and Succulent Society of Australia. Archived from the original on 2008-07-20. Retrieved 2008-07-29.
  2. ^ a b Anderson, Edward F.; Eggli, Urs (2005). Das grosse Kakteen-Lexikon (in German). Stuttgart (Hohenheim): Ulmer. p. 517. ISBN 3-8001-4573-1.
  3. ^ Hochstätter, Fritz (2005). Tribe Cacteae, Family Cactaceae: The genera Pediocactus Navajoa Toumeya. Mannheim: Fritz Hochstätter. p. 10. ISBN 978-3-00-021244-4.