Ceratozamia chimalapensis Perez-Farr . & Vovides, Bot. J. Linn. Soc. 157: 169. 2008

Martinez-Dominguez, Lili, Nicolalde-Morejon, Fernando, Vergara-Silva, Francisco & Stevenson, Dennis Wm., 2022, Monograph of Ceratozamia (Zamiaceae, Cycadales): an endangered genus, PhytoKeys 208, pp. 1-102 : 1

6. Ceratozamia chimalapensis Perez-Farr. & Vovides, Bot. J. Linn. Soc. 157: 169. 2008

Fig. 15F

Type.

Mexico. Oaxaca: Chimalapa , 21 Jan 2002, M.A. Pérez-Farrera 2622 ♀ (holotype: HEM [n.v.]; isotypes: XAL [XAL0146074], MEXU [n.v.], MO [n.v.]) .

Description.

Stem 20-60 cm long, 15-30 cm in diameter, epigeous, erect and decumbent. Cataphylls 4-7.5 × 2.5-4.3 cm wide at the base, persistent, triangular, reddish brown, scarce brown tomentose at emergence, glabrous at maturity, apex acuminate. Leaves 7-24, 66-250 cm long, ascending, brown at emergence, glabrous at maturity. Petiole 40-70 cm long, terete, linear, green in mature leaves; with 20-30 thin prickles, 0.05-0.30 cm long. Rachis 60-150 cm long, terete, linear, green in mature leaves, with prickles. Leaflets 36-70 pairs, opposite to subopposite, insertion in one plane, lanceolate, longitudinally curved abaxially to planar, not basally falcate, papyraceous, flat, light green with adaxial and abaxial sides glabrous, distal end with entire margins, acuminate and symmetrical at the apex, attenuate at base, with conspicuous and green-light veins; median leaflets 27-46 × 1.2-1.8 cm, 0.8-1.3 cm between leaflets; articulations 0.5-0.9 cm wide, brown to yellowish brown. Pollen strobili 25-40 cm long, 3-5 cm in diameter, solitary, cylindrical, erect, greenish yellow at emergence with few brown trichomes, greenish to cream at maturity; peduncle 5-11 cm long, 1.5-3 cm in diameter, reddish brown pubescent; microsporophylls 1.3-2 × 0.6-1 cm, elliptic with a non-recurved distal face and a lobate to slightly lobate fertile portion, infertile portion 0.7-1.1 cm long and linear with curved horns 0.30-0.43 cm long, 0.8-1.1 cm and an acute angle between the horns. Ovulate strobili 35-40 cm long, 7.3-10.6 cm in diameter, solitary, cylindrical, erect, green with blackish trichomes at emergence, green with blackish trichomes at maturity, acuminate apex; peduncle 7-11 cm long, 1.7-2 cm in diameter, erect, brown to reddish brown pubescent; megasporophylls 99-192, 11-12 orthostichies with 9-16 sporophylls per orthostichy, 4-5.9 × 1.8-2.5 cm, with a prominent distal face, horns straight and thin and 0.78-0.98 cm long, 0.98-2.0 cm between horns with an acute angle between the horns. Seeds 2.0-3.0 cm long, 1.4-1.9 cm in diameter, ovate, sarcotesta whitish yellow to yellow when immature, light brown at maturity.

Distribution and habitat.

Ceratozamia chimalapensis is endemic to Oaxaca State (Mexico) in the Sierra Atravesada mountain range at 290-1,000 m (Fig. 16B ) in oak forest on clay soils.

Etymology.

The specific epithet is in honor of the Chimalapa region renowned for its biological richness, particularly its floristic diversity.

Common names.

Mexico. Oaxaca: Mazacopa ( Vovides et al. 2008).

Uses.

The sarcotesta of seeds is used as food; the ground seed is used as a rodenticide and with honey added, used as an insecticide ( Vovides et al. 2008).

Preliminary conservation status.

Ceratozamia chimalapensis is only known from a narrow area with several individuals. Data are insufficient to propose a conservation status at this time.

Discussion.

Ceratozamia chimalapensis is similar to C. mirandae and C. alvarezii in leaf morphology; however, there are differences in reproductive structures; the ovulate strobilus of C. chimalapensis is longer than in these species. The ovulate strobili have between 11-12 orthostichies with 9-16 sporophylls per orthostichy, and more than 90 seeds per strobilus. The seeds are ovate, whereas in the other two species, they are spherical.

Specimens examined.

Mexico. Oaxaca: Mun. Santa María Chimalapa, 290 m, 11 Jun 1995, R. García S. 319 (SERO, XAL). Mun. Santiago Niltepec, 1000 m, 3 Apr 1946, E. Hernández Xolocotzi & A.J. Sharp 1277 (MEXU) .

Figures

Figure 15. Plants of Ceratozamia in habitat A C. alvarezii B C. aurantiaca C C. becerrae D C. brevifrons E C. chamberlainii F C. chimalapensis G C. decumbens H C. delucana I C. euryphyllidia J C. fuscoviridis K C. hondurensis L C. huastecorum.

Figure 16. Distribution of Ceratozamia species A C. chamberlainii B C. chimalapensis C C. decumbens D C. delucana.