Accepted Scientific Name: Sclerocactus brevihamatus subs. tobuschi (W.T.Marshall) N.P.Taylor
Piante Grasse 15(1): 8. 1995
Ancistrocactus tobuschii (Sclerocactus brevihamatus subs. tobuschi) Photo by: Valentino Vallicelli
Origin and Habitat: This rare plant is known from about 200 to about 500 individual specimens on the eastern part of the Edwards Plateau in southern Texas, USA
Habitat: This cactus grows in plains, rock hilltop and floodplain on very shallow gravelly, calcareous soil over limestone rocks, in open areas with only short grass cover within Juniperus ashei-Quercus fusiformis plant association. Threats to the species include collecting and development in its habitat.
Synonyms:
See all synonyms of Sclerocactus brevihamatus
Common Names include:
ENGLISH: Tobusch fishhook cactus
Description: Sclerocactus brevihamatusSN|25266]]SN|25266]] subsp. tobuschii is a small deep-seated cactus with hooked spines. The plant is usually solitary and almost identical to the standard species but with fewer radial spines, flatter stems and with flower tending to appear a little late.
Roots: Short central taproot with a lot of fine fibrous, diffuse roots.
Stem: Unbranched, globose to nearly flat flattened, often inconspicuous, dark green to grey-green, 5-7,5 cm high, up to 10 cm in diameter. The stems of immature specimens, are not obscured by spines.
Ribs: 10-12 completely divided into tubercles.
Tubercles: 5-12 mm high with shallow woolly grooves on upper surface on their entire length.
Areoles: Nearly circular with short whitish wool.
Central spines: 1-5 (mostly 4), light yellow with red tips, uppermost two V-shaped (often with 1 or 2 extra smaller centrals), 20-45 cm long, lowermost one always hooked at the tip, like a fishhook, 22-30(45) mm long.
Radial spines: 7-9 irregularly spreading white or greyish, straight, needle-like, 10-20 mm long.
Flowers: Diurnal, funnelform, inconspicuous, from the adaxial edge of the areoles an the top of the plant, 2,5-3 cm long, 2,5-4 cm in diameter, opening fully, greenish-yellow, light yellow or creamy white, sometime with reddish-brown central strips. Filaments and anthers yellowish. Stigma lobes green, yellow, or whitish.
Blooming season: Flowering late February though April. The flower may open again on the second day.
Fruits: Elongate egg-shaped, thin walled, about 15-30 mm long, 1-1.5 cm wide, fleshy, nearly naked, greenish, ripening to pink or pinkish- brown by late spring or early summer.
Seeds: Kidney-shaped 1,7-2 mm long, dark brown to black and shinning.
Subspecies, varieties, forms and cultivars of plants belonging to the Sclerocactus brevihamatus group
- Sclerocactus brevihamatus (Engelm.) D.R.Hunt: (subsp. brevihamatus) has 12-22 radial spines, larger and more cylindrical stems and the flowers are dusky rose to yellowish-pink or olivaceous in late February-March. Distribution: Edwards Plateau of Texas southern and western border.
- Sclerocactus brevihamatus subs. tobuschi (W.T.Marshall) N.P.Taylor: has nearly flat body, 7-9 irregularly spreading radial spines and hooked central spines, flowers are light yellow to cream flowers in late March-April. Distribution: Edwards Plateau.
Bibliography: Major references and further lectures
1) Sutton, K., et al. (1997). “Habitat of Ancistrocactus tobuschii (Tobusch fishhook cactus, Cactaceae) on the Edwards Plateau of Central Texas.” Southwestern Naturalist 42:4 441.
2) Lyman David Benson “The cacti of the United States and Canada” Stanford University Press, 1982
3) Marshall, W.T. “A new and interesting cactus from Texas” Saguaroland Bull. 6(7):78-81, 1952
4) Albert Michael Powell, James F. Weedin “Cacti of the Trans-Pecos and Adjacent Areas”
Texas Tech University Press, 30/Nov/2004
5) Del Weniger “Cacti of Texas and neighboring states: a field guide” University of Texas Press, 1984
6) Edward Anderson “The Cactus family” Timber Press, Incorporated, 2001
7) Nathaniel Lord Britton, Joseph Nelson Rose “Cactaceae: Descriptions and Illustrations of Plants of the Cactus Family” vol. 4 The Carnegie Institution of Washington, Washington 1923
8) 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
9) David R Hunt; Nigel P Taylor; Graham Charles; International Cactaceae Systematics Group. "The New Cactus Lexicon" dh books, 2006Jackie M. Poole, William R. Carr, Dana M. Price, Jason R. Singhurst “Rare plants of Texas: a field guide” Texas A&M University Press, 30/Dec/2007
10) Brian Loflin, Shirley Loflin “Texas Cacti” Texas A&M University Press, 2009
11) Fritz Hochstätter “The Genus Sclerocactus, Cactaceae, Revised: Magnificent, Fascinating Natural Wonder : Description, Distribution, Cultivation” F. Hochstätter, 1993
12) Proceedings of the American Academy of Arts and Sciences. Boston 3: 270, 1856
13) Bradleya. 9: 91.1991
Ancistrocactus tobuschii (Sclerocactus brevihamatus subs. tobuschi) Photo by: Valentino Vallicelli Ancistrocactus tobuschii (Sclerocactus brevihamatus subs. tobuschi) Photo by: Valentino Vallicelli Ancistrocactus tobuschii (Sclerocactus brevihamatus subs. tobuschi) Photo by: Alexander Arzberger Send a photo of this plant.The gallery now contains thousands of pictures, however it is possible to do even more. We are, of course, seeking photos of species not yet shown in the gallery but not only that, we are also looking for better pictures than those already present.
Read More... 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, but plants grafted on an hardy stock are easy to grow and no special skill is required.
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 they 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 quite difficult to germinate and a low rate of success, seedling did not do well either, and some 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.