The type locality is in the Sierra Madre del Sur. Although first collected in 1925, the species was not formally described until 1982 (Jones 1993).
"A small cycad which in nature develops a slender trunk to about 50 cm long and 10 cm across. Young leaves densely covered with brown hairs. Mature leaves a few in an attractive crown, 1-2 m long, dark green, smooth, glabrous; petiole 20-30 cm long, swollen at the base, armed with sharp prickles; rhachis spirally twisted; leaflets 100-160 on each leaf, 20-50 cm × 0.3-1 cm, linear, sessile, the margins inrolled, apex long tapered, acute to acuminate. Male cones 20-25 cm × 5-8 cm, usually solitary, cylindrical, tawny brown; sporophylls 1.2-1.5 cm × 0.5-0.8 cm, broadly wedge-shaped, with two horns 1-3 mm long; peduncle 2-5 cm long, woolly. Female cones 20-40 cm × 9-12 cm, usually solitary, cylindrical, olive green; sporophylls 2-4 cm × 1.5-3.5 cm, peltate with two stout horns. Seeds 2-3.5 cm × 1.2-1.5 cm, ovoid, smooth, white when ripe.
"Plants can be confused with C. zaragozae which also has spirally twisted leaves but C. norstogii has longer fronds (to 2 m long), ovoid seeds and the apices of its leaflets contract more abruptly to a point. Although the spirally twisted rhachis is usually mentioned as distinctive in this species, it should be noted that some populations do not have this feature" (Jones 1993).
Mexico: Chiapas, on mountain slopes in shady forests dominated by species of Pinus and Quercus. "Natural populations of this species were decimated by overcollecting soon after its description. Following this poaching, many researchers adopted a policy of not including detailed localities when describing new species of cycads" (Jones 1993).
Grown, albeit rarely, as an ornamental (Jones 1993).
Named after Knut Norstog, a contemporary American research worker specialising in cycads (Jones 1993).
The leathery inrolled leaflets represent a morphological adaptation to the seasonally dry climate (Jones 1993).
Pérez-Farrera, M.A., A.P. Vovides, and C. Iglesias. 2001. The cycad Ceratozamia norstogii D.W. Stev. (Zamiaceae) from southern Mexico: new information on distribution, habitat and vegetative morphology. Botanical Journal of the Linnean Society 137:71-76. ABSTRACT: The type locality in Chiapas of the rare and endangered Mexican cycad Ceratozamia norstogii D.W. Stev., originally collected by C.A. Purpus in 1925, has been found. This enabled us to emend and illustrate the description of C. norstogii, thus clearing up some confusion surrounding the concept of this species. We believe the confusion arose owing to a composite herbarium voucher consisting of unrelated material from apparently different physiographic regions of Chiapas. Two further localities for C. norstogii have also been discovered, one in the neighbouring state of Oaxaca. Additional information on its habitat and distribution is presented.
Last Modified 2017-12-29