Origin and Habitat: This wide-ranging species is distributed Mexico (Chihuahua, Coahuila, Durango, Nuevo Leon, San Luis Potosi, Sonora, Zacatecas and Tamaulipas) and USA (southern Texas)
Atitude: It grows at elevations of 900 to 1550 metres above sea level.
Habitat and Ecology: The species occurs in xerophyllous scrub on limestone or calcareous soils. Sclerocactus uncinatusSN|3479]]SN|3479]] is scattered and not abundant, it is not affected by any known major threat. The habitat of Sclerocactus uncinatusSN|3479]]SN|3479]] is home to succulent flora and is particularly rich in local endemics such as: Echinocereus pectinatusSN|7817]]SN|8503]], Echinocereus stramineusSN|8503]]SN|7817]], Escobaria strobiliformisSN|10121]]SN|10121]], Astrophytum crassipinoides, Ariocarpus retususSN|2079]]SN|2079]], Ferocactus steinesii, Neolloydia matehualensisSN|31290]]SN|31290]], Mammillaria candidaSN|9015]]SN|9015]], Lophophora williamsiiSN|1117]]SN|1117]], Thelocactus bicolorSN|15814]]SN|3420]], Thelocactus heterochromusSN|3420]]SN|15814]], Astrophytum myriostigma v. tulense, Echinocactus horizonthaloniusSN|1711]]SN|1711]], Agave lechuguillaSN|23013]]SN|23013]], Fouquieria splendensSN|15717]]SN|15717]] and many other.

• Sclerocactus uncinatus (Galeotti) N.P.Taylor
• Ancistrocactus uncinatus (Galeotti) L.D.Benson
• Echinocactus uncinatus Galeotti
• Echinomastus uncinatus (Galeotti) F.M.Knuth in Backeb. & F.M.Knuth
• Ferocactus uncinatus (Galeotti) Britton & Rose
• Glandulicactus uncinatus (Galeotti) Backeb.
• Hamatocactus uncinatus (Galeotti) Galeotti ex Borg
• Thelocactus uncinatus (Galeotti) Buxb.

• Sclerocactus uncinatus (Galeotti) N.P.Taylor
• Ancistrocactus uncinatus (Galeotti) L.D.Benson
• Echinocactus uncinatus Galeotti
• Echinomastus uncinatus (Galeotti) F.M.Knuth in Backeb. & F.M.Knuth
• Ferocactus uncinatus (Galeotti) Britton & Rose
• Glandulicactus uncinatus (Galeotti) Backeb.
• Hamatocactus uncinatus (Galeotti) Galeotti ex Borg
• Thelocactus uncinatus (Galeotti) Buxb.

• Sclerocactus uncinatus subs. crassihamatus (F.A.C.Weber) N.P.Taylor
• Ancistrocactus crassihamatus (F.A.C.Weber) L.D.Benson
• Ancistrocactus uncinatus subs. crassihamatus (F.A.C.Weber) Doweld
• Echinocactus crassihamatus F.A.C.Weber in Bois
• Ferocactus crassihamatus F.A.C.Weber in Bois
• Glandulicactus crassihamatus (F.A.C.Weber) Backeb.
• Hamatocactus crassihamatus (F.A.C.Weber) Buxb.
• Hamatocactus uncinatus subs. crassihamatus (F.A.C.Weber) Glass
• Pediocactus uncinatus var. crassihamatus (F.A.C.Weber) Halda
• Sclerocactus uncinatus var. crassihamatus (F.A.C.Weber) N.P.Taylor
• Thelocactus crassihamatus (F.A.C.Weber) W.T.Marshall

• Sclerocactus uncinatus subs. crassihamatus var. mathssonii (Berge ex K.Schum.) nov. comb. ined.
• Ancistrocactus mathssonii (Berge ex K.Schum.) Doweld
• Echinocactus mathssonii Berge in K.Schum.
• Ferocactus mathssonii (Berge ex K.Schum.) N.P.Taylor
• Glandulicactus mathssonii (Berge ex K.Schum.) D.J.Ferguson

• Sclerocactus uncinatus subs. wrightii (Engelm.) N.P.Taylor
• Ancistrocactus uncinatus subs. wrightii (Engelm.) Doweld
• Ancistrocactus uncinatus var. wrightii (Engelm.) L.D.Benson
• Echinocactus uncinatus var. wrightii Engelm.
• Echinocactus uncinatus f. wrightii (Engelm.) Schelle
• Echinocactus wrightii (Engelm.) J.M.Coult.
• Echinomastus uncinatus var. wrightii (Engelm.) F.M.Knuth
• Echinomastus uncinatus f. wrightii (Engelm.) Scheele
• Ferocactus uncinatus var. wrightii (Engelm.) N.P.Taylor
• Glandulicactus uncinatus subs. wrightii (Engelm.) U.Guzmán
• Glandulicactus uncinatus var. wrightii (Engelm.) Backeb.
• Glandulicactus wrightii (Engelm.) D.J.Ferguson
• Hamatocactus uncinatus var. wrightii (Engelm.) Bravo
• Hamatocactus wrightii (Engelm.) Orcutt
• Pediocactus uncinatus var. wrightii (Engelm.) Halda
• Sclerocactus uncinatus var. wrightii (Engelm.) N.P.Taylor
• Thelocactus uncinatus var. wrightii (Engelm.) H.P.Kelsey & Dayton
• Sclerocactus uncinatus subs. wrightii f. cristatus hort.
• Ancistrocactus uncinatus subs. wrightii f. cristatus hort.
• Echinocactus uncinatus var. wrightii f. cristatus hort.
• Echinomastus uncinatus var. wrightii f. cristatus hort.
• Ferocactus uncinatus var. wrightii f. cristatus hort.
• Glandulicactus uncinatus subs. wrightii f. cristatus hort.
• Glandulicactus wrightii f. cristatus hort.
• Hamatocactus wrightii f. cristatus hort.
• Pediocactus uncinatus var. wrightii f. cristatus hort.
• Thelocactus uncinatus var. wrightii f. cristatus hort.

Description: Sclerocactus uncinatusSN|3479]]SN|3479]] (more often listed under its old name Glandulicactus uncinatusSN|3474]]SN|3474]]) is a solitary cylindrical cactus. Three subspecies are recognized, the nominate form, subsp. crassihamatus (F.A.C.Weber) N.P.Taylor and subsp. wrightii (Engelm.) N.P.Taylor .
Stem: Up to 20 cm tall, 8 cm in diameter.
Ribs: Approx.13, strongly crenate.
Areoles: Elongated on sexually mature plants.
Areolar gland: Dome-shaped.
Central spine: 1 hooked.
Radial spines: 7 or 8 reddish straight ones, but the abaxial radial spines are consistently hooked, too.
Flowers: Broadly funnel-form-campanulate, diurnal, dull pink to dark red, or russet or brownish purple to almost black, 2-4 cm long, up to 3 cm in diameter.
Blooming time: In spring.
Fruit: Showy red.

Bibliography: Major references and further lectures
1) Edward Anderson “The Cactus family” Timber Press, Incorporated, 2001
2) James Cullen, Sabina G. Knees, H. Suzanne Cubey "The European Garden Flora Flowering Plants: A Manual for the Identification of Plants Cultivated in Europe, Both Out-of-Doors and Under Glass" Cambridge University Press, 11/Aug/2011
3) David R Hunt; Nigel P Taylor; Graham Charles; International Cactaceae Systematics Group. "The New Cactus Lexicon" dh books, 2006
4) Goettsch, B.K., Terry, M., Heil, K. & Corral-Díaz, R. 2013. Sclerocactus uncinatus. In: IUCN 2013. "IUCN Red List of Threatened Species." Version 2013.2. <www.iucnredlist.org>. Downloaded on 18 February 2014.

Cultivation and Propagation: This plant is relatively rare in cultivation and has the fame to be difficult to grow on its own roots because it is very sensitive to overwatering (rot prone) and slow-growing. This species is extremely xerophytic, cold hardy and adapted to very dry soils.
Soil: Grow it in an open mineral, sandy-gritty cactus compost.
Pots: It needs a relatively large or deep pot to accommodate its extensive roots and provide a very good drainage. They may stay in the same pot for many years.
Watering: Water it sparingly and keep it completely dry during winter or when night temperatures remain below 10° C. Mature individuals easily rot and die especially after planting so be extremely cautious with watering. Water it less than average if in bigger pots.
Special need: Provide very good ventilation. Nearly all problems occur as a result of overwatering and poor ventilation, especially when weather conditions are dull and cool or very humid. They must have very dry atmosphere.
Fertilization: Feed them once during the growing season with a fertilizer specifically formulated for cactus and succulents (high potash fertilizer with a dilute low nitrogen), including all micro nutrients and trace elements diluted to ½ the strength recommended on the label. They thrive in poor soils and need a limited supplies of fertilizer to avoid the plants developing excess vegetation, which is easily attacked by fungal diseases.
Exposure: It will do its best with lots of sun and become stressed with inadequate light which could result in poor growth and unnatural shape.
Hardiness: An unheated greenhouse would be perfect. It can survive low temperatures, approx. -7° (-12°) C.
Use: This is a good pot plant suited for a non heated green house. It can be also cultivated outdoors in raised beds, terraces if sheltered from winter rain. This cactus continues to be, a particular prize among collectors.
Pests & diseases: These cacti may be attractive to a variety of insects, but plants in good condition should be nearly pest-free, particularly if they are grown in a mineral potting-mix, with good exposure and ventilation. Nonetheless, there are several pests to watch for:
- Red spiders: Red spiders may be effectively rubbed up by misting the plants from above.
- Mealy bugs: Mealy bugs occasionally develop aerial into the new leaves and flowers with disfiguring results, but the worst types develop underground on the roots and are invisible except by their effects.
- Scales, thrips and aphids: (they are rarely a problem.)
- Rot: Rot is only a minor problem if the plants are watered and “aired” correctly. If they are not, fungicides won't help all that much.
Propagation: Seeds are relatively easy to germinate, but some seedling die each year. The seeds can be sown in pots of fine, well-drained sandy soil, any time during the spring when temperatures are warm. Cover the seeds with a fine layer of grit and water from below with a fungicide to prevent damping off. For the 1-2 weeks cover the pots with a sheet of glass/clear perspex to keep the humidity levels high. Remove the glass and replace it with light shade-cloth and mist once or twice a day for the next two weeks after which most seeds should have germinated. From then on mistings can be reduced to every second and then every third day as the little plants grow. Grafting is often used to speed growth rate and to create a back-up for plants in collection.