(Picture = Hawortial koelmaniorum)
Haworthia koelmaniorum is a rare plant endemic to Mpumalanga, South Africa. It is slow growing, and its ecology is poorly understood. Better knowledge is required to prepare conservation plans.
Details
The seven known populations of H. koelmaniorum were studied. Population size varied from 25 to 588 individuals, with 1591 plants in total. Size (leaf number per plant or rosette diameter) did not vary between populations. However, no seedlings were found. Overall, 67% of plants were damaged by fire and or animals, but all appeared to survive fire. The percentage of plants flowering per population varied from 24-76%. Percentage germination was high (78- 88%), but seeds apparently have short-term (5-7 month) persistence, and thus no seed bank is formed. Plants grow preferentially within rock fissures. These situations were characterized by a high cover of fixed and exposed rock, high overstorey shade, low understorey shade and live vegetation cover. These sites have reduced competition from other plants and are suitable for slow-grown rare plants. Seedling establishment is likely linked to high rainfall periods (probably several years of clement weather), and seeds are apparently dispersed to the few safe rock fissures (safe sites) available.
H.koelmaniorum should remain in the Vulnerable IUCN category due to herbivory, fire, small population sizes, low rates of seedling establishment and a very restricted distribution.
Additional Reading: Infrageneric Classification of Haworthia
Additional Reading: https://www.haworthia.com/