Etymology: Named after the Mexican conservationist Miguel Alvarez del Toro. Distinguishing features: A small highly branched Ceratozamia species thought to be related to C. matudae. C. alvarezii is distinguished from C. matudae by the more branched habit and the thick erect peduncle of the female cones (the peduncle is long, thin and decumbent in C. matudae). C sabatoi differs in having wider, longer leaflets and bluish seed cones. C. norstogii is a larger plant with an unbranched trunk and spirally twisted leaf rachises. Distribution and habitat: Known only from a small area in the Sierra Madre de Chiapas, in moist pine-oak forest with a fern rich ground layer at about 950 m elevation. Conservation status: Considered to be endangered by habitat loss as the forests are being cleared for agriculture. Not listed by the 1997 IUCN Red List of Threatened Plants. Description:
Plants acaulescent (branching freely); stem 10-50 cm long, stem 9-18 cm diam. Leaves 4-18 in crown. New growth emerging bronze, red or chocolate brown. Leaves dark green, semiglossy, 50-110 cm long, flat (not keeled) in section, with 24-62 leaflets; vernation straight; rachis not or slightly spirally twisted; petiole 14-42 cm long. Leaflets not clustered, linear, symmetric, broadest below middle, not falcate, strongly discolorous, thick or leathery; margins flat; median leaflets 16-33 cm long, 4-9 mm wide. Cataphylls 21-50 mm long, brown. Pollen cones yellow-green (to cream), narrowly ovoid-cylindrical, 11-31 cm long, 2.5-4.5 cm diam.; peduncle 4-5 cm long; microsporophyll lamina 14-17 mm long, 6-9 mm wide. Seed cones brown, ovoid-cylindrical, 14.5-19 cm long, 5.7-10.5 cm diam.; peduncle 4.5-6.5 cm long; megasporophyll 28-45 mm long, with an expanded peltate apex 15-29 mm wide. Seeds ovoid, 17-25 mm long, 17-20 mm wide; sarcotesta white, aging to
brown.
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