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| Kingdom | Plantae |
| Phylum | Tracheophyta |
| Class | Magnoliopsida |
| Order | Caryophyllales |
| Family | Cactaceae |
| Genus | Thelocactus (1) |
Thelocactus hastifer can be immediately recognised by its elongated stem, which may be erect or lie along the ground (‘decumbent’). This elongate stem is a unique character among the species of this genus, and even young seedlings can be easily distinguished from other Thelocactus species by the elongate rather than rounded growth. Individual plants have a swollen root and a thin stem, about 5.5 centimetres in diameter, which is divided into 13 to 18 ribs. In older individuals, the stem branches from the base. The main body of the plant has a very thin collar between the root and the upper part of the stem, which is unable to bear the weight of the stem, so that it eventually grows lying on the ground. The spines of this cactus are straight and needle-like, and consist of 20 to 25 ‘radial’ spines, which are white in colour and measure up to 1.5 centimetres long, and 4 to 5 ‘central’ spines, which are longer, at up to 2.6 centimetres, and whitish to black in colour (4).
Thelocactus hastifer flowers from February to May, producing magenta flowers that measure 3.5 to 7.5 centimetres wide. The flowers open from midday to early afternoon and last one or two days (4) (5). The fruits, which are relatively small for the genus, mature from March to July, and the shiny black seeds are released from an opening at the base of the fruit. The reproductive rate of this cactus is considered to be low, as only 30 seeds are produced on average per plant per year (5).
TopFound only in few localities in the municipality of Cadereyta de Montes, Querétaro, Mexico (5).
TopThis species grows on limestone hills at altitudes of 1,800 to 2,050 metres above sea level, where it is associated with desert scrub habitat (5).
TopClassified as Vulnerable (VU) on the IUCN Red List (1) and listed on Appendix II of CITES (3).
TopHuman activities are the main factors affecting the populations of this cactus. Land conversion for agricultural purposes, grazing, and expansion of populated areas are reducing its habitat, while illegal collection can also affect population size (5).
TopThelocactus hastifer is listed on Appendix II of the Convention on International Trade in Endangered Species (CITES), which permits trade of wild plants in a controlled way to avoid utilization incompatible with their survival (3). Within Mexico, the species is also subject to special protection (Pr) on the Norma Oficial Mexicana NOM-059 (6). The area where Thelocactus hastifer grows is rich in rare and threatened cacti, and setting it aside as a natural reserve should be considered (2).
TopTo find out more about Thelocactus species see:
Information supplied and authenticated (26/06/2010) by Alessandro Mosco, PhD, Department of Life Sciences, University of Trieste.
http://www.thelocactus.cactus-mall.com/
More »Related species
Image credit
© Alessandro Mosco
Alessandro Mosco
webmaster@thelocactus.cactus-mall.com
http://www.thelocactus.cactus-mall.com/
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