Cycad

Ceratozamia norstogii D.W.Stev.

Ceratozamia norstogii is a cycad species in the Zamiaceae family, native to southwestern Mexico. It is classified as Endangered due to habitat loss. The species is characterized by its twisted petiole and rachis, coriaceous linear leaflets that are strongly involute and caniculate, and an acute apex. It was named in honor of Knut Norstog for his contributions to cycad biology.

Description

Ceratozamia norstogii has a stem 30–60 cm long, 20–40 cm in diameter, and is either erect or decumbent. The cataphylls are persistent, long triangular, and reddish brown. Leaves are 50–126 cm long, with copperish brown coloration at emergence and glabrous at maturity. The petiole is 10–49 cm long, twisted, and has 30–60 prickles. Leaflets are 14–48 mm wide, with a yellowish adaxial surface and glaucous abaxial surface. Pollen strobili are 13.2–25 cm long, cylindrical, and solitary. The species is easily identified by the twisted petiole and rachis and the strongly involute leaflets.