Opuntia chlorotica chlorotica

Opuntia chlorotica
Opuntia chlorotica

Engelmann & Bigelow, Proceedings of the American Academy of Arts and Sciences 3: 291, 1856

Holotype; Lectotype; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; HerbariumDrawing (Botany of the Expedition, 1856, plate VI)

Original Description

What is Opuntia chlorotica chlorotica?

O. chlorotica chlorotica is the prickly pear cactus that summons up visions of gunfights and posses. It is one of three varieties: chlorotica, santa-rita, and gosseliniana within the O. chlorotica complex as described by Ferguson (1988). The three types blend into each other over their range. 

Details

Plants of this O. chlorotica variety may reach 2(2.5) m tall and usually form a single trunk that can reach 20 to 30 cm in diameter. Plants are often upright, but some spreading may occur. Cladodes are suborbicular or orbicular and may be about 12(20) cm across all diameters. Yellow, deflexed spines (2-6), 1-3 cm long, are present in most areoles. Though most populations have very spiny pads, some populations are almost spineless (as near Congress, Arizona). Typically the trunk is covered with stout spines up to 5 cm long. Glochids can become prominent and robust on older pads, up to nearly 2 cm long. 

O. chlorotica chlorotica has modest, yellow flowers about 2 inches across. A pale red blush may occur on the interior near the base of tepals. The abaxial tepals may have pale reddish veins. Filaments are white to yellow. Anthers, style, and stigma are white, yellowish, or pale green. Fruit is semi-spherical, egg-shaped, or barrel-shaped, 30-60 × 18-40 mm.  The fruit pulp of this prickly pear is often colorless and without flavor. Seeds are yellowish, approximately 3.5-4 × 3-3.5 mm, reniform to subcircular, flattened or warped, with a 0.1-0.5 mm girdle. 

O. chlorotica is diploid.

Other Notes

The plant is found in southern Nevada, southeastern California, much of Arizona, and barely into southwestern Utah. It is also found in extreme southwest New Mexico.  Typically, O. chlorotica chlorotica grows in well-drained, rocky soils, sometimes between boulders or on cliff faces. However, this Opuntia species may grow in deep, sandy soils such as near Wickenburg, Arizona. 

 

Opuntia camanchica

Opuntia camanchica
Opuntia camanchica

Engelmann & Bigelow, Proceedings of the American Academy of Arts and Sciences 3: 293, 1856/1857

Herbarium; Herbarium; Herbarium; Herbarium (as O. phaeacantha); Herbarium (as O. phaeacantha); Herbarium (as O. phaeacantha); Herbarium (as O. phaeacanthaHerbarium (as O. phaeacantha); Herbarium (as O. phaeacantha); Herbarium (as O. phaeacantha); Herbarium (as O. phaeacantha); Herbarium (as O. phaeacantha); Painting; PaintingDrawing (Bigelow, J.M., The Botany of the Expedition, 1856, plate IX No. 1-5)

O. camanchica shares similarities with O. dulcis

O. camanchica shares similarities with O. phaeacantha

Original Description

What is Opuntia camanchica?

Opuntia camanchica is a handsome and widespread prickly pear cactus found throughout southwest Texas to western Arizona and into southern Colorado. Many plants have long, stout, dark spines and large flowers.  

Details

From Powell and Weedin: 

Opuntia camanchica is a cactus similar in habit to O. phaeacantha, but it is a woodier plant (it has more substantial supportive tissues in its stems). Thus, under comparable conditions, it grows into a taller prickly pear than O. phaeacantha and remains more erect in winter. Also, the sprawling stems of this Opuntia are stiffer than those of O. phaeacantha. The plants are usually less than 70 cm tall. There is much variation in spine number and color (pale, red, white, black, brown, purplish), which is in contrast to O. phaeacantha, which often (not always) has pale spines on the sides of pads. The spines are stout and especially prominent on distal areoles where there may be 3-4(6) that diverge in several directions. Spines on this Opuntia may have slight curvature.

Flowers are yellow with red centers, 5-7 cm long and wide—often opening less widely than those of O. phaeacantha or O. dulcis. Filaments are 1.5-1.7 cm long and wide and cream colored. Anthers are yellow and about 2 mm long. The style is cream, about 2 cm long, with cream-colored, green, or dark green lobes. The pericarpel is 3-5 cm long with scattered areoles with no spines, except perhaps a few small spines in distal areoles. This Opuntia has pretty flowers because of the red centers, which may be strawberry red. 

Red or cherry-red fruits are 3.7-5(-6.7) cm long, 2.3 to 3.3 cm wide and typically have a deep umbilicus. The fruits are spineless except they may have 1-2 spines near the rim. There are relatively few areoles. Fruit pulp is green and juice is clear, but the juice is not sweet and is not abundant. The rind may be colorless. Alternately, fruits may have a reddish pulp and abundant juice. Thus the fruits may vary somewhat on this Opuntia. The seeds are 4 to 5 mm in diameter, irregularly discoid with a broad hilar notch and a prominent aril that is 0.5 mm wide (or more).

O. camanchica is hexaploid.

Other Notes

O. camanchica is another prickly pear often lumped with O. phaeacantha. The two are different but related species. O. camanchica is often a taller plant because it is woodier and can support taller, upright branches. O. camanchica may spread to 1.0 to 1.2 m across in a mound, or it may be more irregular and semi-prostrate and sprawling. The areoles are relatively far apart and the pads are thickish by comparison with O. phaeacantha. The often circular-appearing cladodes and stout spines make this Opuntia distinct throughout its range even while spines can vary in coloration or length. O. camanchica grows throughout much of NM and western TX and is also found in AZ, UT, and CO.

Some plants have rich red-brown or blue-black spines and are handsome garden plants. Upright branches may reach 50 cm or taller in a garden.  

Opuntia charlestonensis

Opuntia charlestonensis
Opuntia charlestonensis

Clokey, Madrono 7(3): 71, 1943

Isotype; Isotype; Isotype; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium

Original Description

What is Opuntia charlestonensis?

Opuntia charlestonensis is a prickly pear cactus that occurs from about 6,000 to 8,000 ft in Kyle Canyon on Mt Charleston, Nevada. It is proposed to be a hybrid taxon derived from two species, O. phaeacantha and O. polyacantha erinacea.

Details

Plants may be 20 to 40 cm tall and up to 1.5 m across. They are generally prostrate, but short branches of a few cladodes may arise from prostrate main branches. Cladodes are oval or obovate and 10-20 cm long and 7-14 cm wide. Cladodes may be strongly purple in the winter and spring. Spines (4-6) are light in color, and spreading in all directions.

O. charlestonensis has yellow or canary-yellow flowers that darken late on the day of anthesis; there may be a blush of red in the flower centers. Flowers are 4-5 cm across. Stamens and anthers are yellow as is the style and stigma. However, the style may be tinged with red. Fruit is oval and dull reddish-purple with a green pulp. Seeds are flat and 4-5 mm in diameter.

O. charlestonensis is pentaploid.

Other Notes

O. charlestonensis is sympatric with the two proposed parental Opuntia species, but O. dulcis also grows in Kyle canyon. This latter Opuntia has not been investigated as a possible parent. 

This prickly pear was originally (1943) only known from Kyle Canyon on Mt. Charleston, NV. However, in 2014 a population of this Opuntia was reported in CA where it also seems to be formed by hybridization. 

Opuntia pottsii

Opuntia pottsii
Opuntia pottsii

Salm-Dyck, Cacteae in Horto Dyckensi Cultae Anno 1849 236, 1850

HerbariumHerbariumHerbariumHerbarium; Herbarium; Herbarium; HerbariumHerbarium (O. ballii); Herbarium (O. ballii)

 Original Description

What is Opuntia pottsii?

Opuntia pottsii is a small prickly pear cactus with colorful flowers. It is found in many regions of the West but it is seldom abundant. It grows from about 4,500 ft to about 9,000 ft. 

Details

Opuntia pottsii is a small prickly pear cactus, sometimes just 10 to 15 cm tall or 25 cm across, often with just 6-10 cladodes. There are (0)1-4(5) spines per areole in the distal portion of the pad. Spines are gray-white to red-brown or rarely yellow, erect or reflexed, terete or proximal ones flattened, sometimes spirally twisted. Spines are slender and the longest may be over 4(5) cm. The cladodes of this Opuntia are dark green, cuneate-obovate to commonly rhombic, 5 to 15(20) cm long and 5 to 7(9) cm wide. The cladodes are fleshy but firm.

Flowers are reddish or pink (sometimes yellow). The style is whitish and the stigma is white to pale yellow. Anthers are yellow. Seeds are tan to gray, subcircular, thick and warped; the girdle protrudes about 0.5 mm. 

O. pottsii is tetraploid. 

Other Notes

Some O. pottsii plants grow upright from a single central stem; the pads do not crawl along the soil as is often the case with many small Opuntia species. Benson (Cacti of United States and Canada, 1983) proposed a very broad concept of O. macrorhiza that included O. pottsii as a distinct variety. In fact, while O. pottsii is variable, it clearly differs from O. macrorhiza by the flower color as well as the long pericarpels and its smaller size. There is enough variation within the species that varieties might be described. A distribution map is provided by the Flora of North America online, but the map is conservative because this prickly pear cactus has been observed in more northerly and more easterly areas by the authors. In fact, O. pottsii occurs in northern Arizona as far west as the Hualapai Mountains, in much of New Mexico, and parts of northwest Texas. 

The plants can be confused with other small opuntias including O. polyacantha and O. macrorhiza if they are only casually observed or if they are growing among grasses, etc. However, O. pottsii is noticed in flower because it has pink, red, orange, or salmon flowers (some plants have yellow flowers with/without red centers). Britton and Rose reported that the type locality for this prickly pear cactus is near Chihuahua, Mexico. Opuntia pottsii is tetraploid.

Because some forms are exceptionally cold hardy and have reddish flowers, O. pottsii is a good garden plant. 

Plants at higher elevations with wider pads and shorter ovaries were described as O. pottsii montana (Succulentes 25, numero special: 40, 2002). O. pottsii montana may be synonymous with O. plumbea Rose 1908 and O. loomisii Peebles 1939. 

Opuntia basilaris

Opuntia basilaris ramosa
Opuntia basilaris ramosa

Engelmann & Bigelow, Proceedings of the American Academy of Arts and Sciences 3: 298, 1856

 

Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; HerbariumHolotype (O. basilaris brachyclada); Herbarium (O.  basilaris brachyclada); Herbarium (O. basilaris brachyclada); Herbarium (O. basilaris brachyclada); Herbarium (O. basilaris longiareolata); Herbarium (O. basilaris longiareolataHerbarium (O. basilaris longiareolata); Herbarium (O. basilaris longiareolata); Isolectotype (O. basilaris ramosa);  Herbaraium (O. basilaris ramosa); Herbarium (O. basilaris heilii); Herbarium (O. basilaris heilii); Herbarium (O. basilaris heilii); Isolectotype (O. basilaris woodburyi); Holotype (O. humistrata); Herbarium (O. basilaris treleasii); Holotype (O. basilaris whitneyana); Painting; Painting; Painting

Original Description

What is Opuntia basilaris?

Opuntia basilaris is a distinctive prickly pear cactus; it has the archetypical “beaver tail” look. Mature plants form dense clumps 15-30 cm tall and 30-100 cm across. The pads are blue-green or grayish-green and are often wedge shaped or broadly obovate. Pads are (7)15-17(22) cm long.

Details

Often the cladodes of this prickly pear are fan shaped, but they may be oval, obovate or even elongate-obovate. The pads of the major variety of this Opuntia (var basilaris) arise from a single point and form an approximate rosette. The areoles are slightly sunken. This prickly pear has blue-green or gray-green pads that are distinctive and that may have hints of purple, or they may be entirely purple under stress. Though spineless, there are numerous small glochids to be avoided.

Flowers are magenta and about 7-8 cm across, very showy. Fruit is dry. They style is white or pinkish-white, and the stigma is  white. Filaments are red, anthers are yellow. The seeds are large and thick (subspheric?) and angular. They measure 6.5-9 × 6.5-7 mm.

O. basilaris basilaris is diploid, but O. basilaris treleasei is triploid.

Other Notes

We recognize five varieties of this Opuntia:

  • basilaris
  • brachyclada
  • longiareolata
  • ramosa
  • treleasei

Britton and Rose discuss several varieties that are not recognized here including: albiflora, coerulea, and nanna. O. basilaris basilaris is by far the most commonly encountered variety. All varieties of this  prickly pear are spineless except var treleasei. 

Native Americans used O. basilaris as a medicinal plant (Anderson, 2001). Perhaps there was some beneficial effect to ingesting the cactus because it contains 3,4-dimethoxyphenethylamine, a compound related to dopamine and mescaline. 

O. basilaris is a favorite in gardens because of its unique shape, pad colors, and bright flowers. Some clones from higher altitudes are cold-hardy. 

Opuntia aurea

Opuntia aurea, Zion
Opuntia aurea, Zion

Baxter, Cactus and Succulent Journal (U.S.) 5(6): 489, 1933

Holotype; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium

Original Description

What is Opuntia aurea?

Opuntia aurea is a prickly pear cactus that grows in southern UT and northern AZ. It is prostrate and forms irregularly sprawling plants to about 1 m across. A single pad may grow upright now and then.

Details

The cladodes are often oval but may also be broadly obovate up to 10(15) cm long. Cladodes have a thick look and they may become pink or purple in winter. Areoles on this Opuntia may be slightly sunken. O. aurea may be spineless or may have a few spines to multiple spines. Spines may be in the distal areoles only or on the faces of the cladode too. Excessively spiny plants may represent introgression from adjacent species. 

Flowers are pale-yellow, yellow, apricot-pink, and even strongly pink. Seeds are often circular and up to 7-8 mm in diameter or a bit more; arils may be 1-2 mm. Fruits of this prickly pear typically have no spines, but there may sometimes be one or more at the apex. Fruit is dry at maturity.

O. aurea is hexaploid.

Other notes. 

Because many plants are without spines, and because the areoles may be sunken, the plant was considered to be closely related to O. basilaris at one time. But, the two are rather different. Perhaps O. aurea has an O. basilaris-type plant in its background. 

O. aurea is a beautiful garden plant and does not become too large if modestly trimmed. Some forms are nicely cold-hardy. Flowers my be yellow, apricot, pink, and magenta. Some forms turn strongly red-purple in the winter. 

Special thanks to the Cactus and Succulent Society Journal for permission to reproduce the original description.

 

Opuntia arenaria

Opuntia arenaria
Opuntia arenaria

Engelmann, Proceedings of the American Academy of Arts and Sciences 3: 301, 1856/1857

Lectotype; IsotypeHerbarium; Herbarium; Herbarium; Herbarium

Original Citation

What is Opuntia arenaria?

O. arenaria is a small prickly pear that occurs in the greater El Paso region from adjacent New Mexico to near McNary, Texas in sandy or silty soils where they form low, creeping cactus mats often 1-3 m in diameter. It has a broader distribution in Mexico. It is described as a variety of O. polyacantha in the Flora of North America. However, we regard this cactus as a stand-alone species of prickly pear. 

The Details

From Powell and Weedin (O. polyacantha var arenaria):

Often some branches of this Opuntia are buried by shifting soil and these have been interpreted by some to be rhizomes. The pads are small and narrow, 4-7(-10) cm long and 2-3(-5) cm wide and 2-3 cm thick. This Opuntia produces spines in all but the lowermost areoles, but the spines do not cover the glaucous or light green stem segments. Areoles may have 5-10 spines with one much longer than the others. The largest and flattest pads of O. arenaria may resemble the pads of O. polyacantha in overall aspect.

The yellow flowers of this prickly pear are 4-6.4 cm long and 4-6 cm wide. The filaments are white or pale tinged with pink, anthers are 1.5 mm long and yellow. The style is while or pale green, 1.2 to 2 cm long. The stigma lobes are about 2 mm long and green. The pericarp is slender, perhaps 2 or 3 times as long as thick.

The fruits are reddish and then tan and dry at maturity in this Opuntia. Fruit areoles may have 3-6 spines that are 6-9 mm long. The fruit is narrowly obovate-obconic, constricted below the apex, 2.5-3 cm long and 0.9-1.2 cm in diameter. The umbilicus is deep. Seeds are tan and shiny, irregularly discoid, and large—up to 6.5 mm in diameter. The have a 1-2 mm margin.

O. arenaria is diploid.

Other Notes

O. arenaria habitat is being destroyed by development, dumping, and off-road driving, etc.  See a report by the NatureServe Explorer

This prickly pear species is closely akin to other dry-fruited species of Opuntia, but due to its low chromosome number and morphological stability, it is usually considered to be a distinct and well-defined species. O. polyacantha (incl. O. erinacea) may be separated by the larger Opuntia (i.e., polyacantha) because the pads in O. polyacantha are usually well over 3 cm in diameter, as well as the fact that individuals of that taxon may have pink, red, or magenta pigmentation in their flowers. Opuntia polyacantha is tetraploid (2n = 44), whereas O. arenaria is diploid (2n = 22). The two Opuntias are not known to occur sympatrically.

Opuntia angustata

Opuntia angustata
Opuntia angustata

Engelmann & J. M. Bigelow, Proceedings of the American Academy of Arts and Sciences 3: 292, 1856/1857

Syntype; Painting (Smithsonian Institution); Holotype (Opuntia magnarenensis); Lectotype (Opuntia magnarenensis); Drawing (The Botany of the Expedition, 1856, plate VII)

Original Citation (O. angustata)

Original Citation (O. magnarenensis)

What is Opuntia angustata?

Opuntia angustata is a poorly understood or documented prickly pear cactus reported from northwestern Arizona and adjacent portions of Nevada and California.

Details

The photos presented here represent our concept of this Opuntia. O. angustata is larger and woodier/stiffer than O. phaeacantha but is smaller than O. engelmannii to which it seems related. Spines are often long and chalky white.

Flowers are yellow. 

Ploidy is unknown. 

Other Notes

Britton and Rose reported that the true type specimen for this Opuntia is from the bottoms of the Bill Williams River in AZ. Engelmann and Bigelow described a prickly pear cactus that had narrow cladodes. O. angustata and O. riparia are similar and may in fact represent the same taxon. O. riparia occurs further south (near Tucson, AZ and below). Also, we interpret O. angustata to be the same as O. magnarenesis described by Griffiths from Owens, AZ (near Wikieup, AZ), which does not have especially narrow cladodes.