Current circumscription of the name
Plants of the World Online accepts Ferocactus peninsulae and gives its native range as the Baja California peninsula in Mexico. F. horridus is a synonym of this species. In contrast, F. townsendianus, formerly also F. peninsulae var. townsendianus, is accepted separately. The 2014 hydration-memory study concerned this second taxon. Its results are in a separate account. [2-WWW] [López-Urrutia et al. 2014]
The stem and strong spines
Under the name F. peninsulae, Britton and Rose described a solitary, erect stem, cylindrical to club-shaped, reaching 2.5 m in height. They gave 12–20 distinct ribs, four central spines and around eleven radial spines. The spines were red with yellow tips. The monograph also notes doubts about the identity of some historical collections, so its size description applies to the material presented there. [Britton and Rose 1922, p. 133–134]
Spherical plants from San Francisquito Bay, collected in 1911, were described as F. horridus. They had 13 broad ribs, 8–12 radial spines and 6–8 central spines. One central spine was flattened, very strongly hooked and often reached 12 cm. The current inclusion of this name in F. peninsulae connects its history with the broader variation of the species. [Britton and Rose 1922, Britton and Rose, p. 128] [2-WWW]
Regeneration from a thin stem fragment
Manokari and colleagues' 2024 study used seedlings originating from fruits of a plant cultivated in a garden in Puducherry, India. Stem fragments of the tTCL type were around 200 µm thick and retained areoles. The abbreviation means a transverse thin cell layer. Propagation depended on activating structures capable of producing new shoots that remained in such a small section. [Manokari et al. 2024]
On medium containing the cytokinin BAP, activation was achieved in 98.6% of explants in the best-performing treatment. At the multiplication stage, combining BAP with the auxin IAA yielded a mean of 19.3 shoots per fragment, with a mean length of 3.5 cm. The experiment had three replicates, with 24 explants per treatment. High regulator concentrations were associated with callus formation and abnormal shoot structure. Callus is a mass of cells proliferating outside the usual organisation of an organ. [Manokari et al. 2024]
At the rooting stage, the best treatment produced roots in 95.8% of shoots. Subsequently, 92% of plants survived greenhouse acclimatisation. The authors reported survival of all already hardened plants after a year in the garden, but gave neither the size of this final group nor detailed data. The final percentage refers to plants that had already passed through selection during acclimatisation. [Manokari et al. 2024]
The study documents efficient propagation of selected material under controlled conditions. Similarity in growth form to the original plant was assessed morphologically. Genome stability and representativeness of wild populations require separate analyses. The result describes development of regenerated plants and their transition from culture medium to growing substrate. [Manokari et al. 2024]
Chemical composition in a separate section
Elansary and colleagues' 2020 study examined methanolic stem extracts from cultivated plants described under names including F. horridus (now F. peninsulae). Analyses covered phenolic compounds and laboratory tests of extract activity. The material and scope of these measurements are presented in the article on ferocactus extracts in the applications section. [Elansary et al. 2020] [2-WWW]
Related articles
Materials from the author's archive
The species also appears in Konrad Szychowski's private material archive. [Kaktusy i Inne 2006a, file p. 42]
Synonyms and names in the literature
Echinocactus peninsulae · Ferocactus horridus [2-WWW]