Ceratozamia zoquorum Pérez-Farr., Vovides & Iglesias. Bot. J. Linn. Soc. 137 (1): 77. 2001

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

36. Ceratozamia zoquorum Pérez-Farr., Vovides & Iglesias. Bot. J. Linn. Soc. 137 (1): 77. 2001

Figs 1D , 23 A-C

Type.

Mexico. Chiapas: Northern mountain range , 18 Nov 1998, M.A. Pe ́rez-Farrera 1732 ♂ (holotype: CHIP [n.v]) .

Description.

Stem 12-30 cm long, 8-15 cm in diameter, epigeous, semi-hypogeous, erect. Cataphylls 2.5-6.9 × 1.3-4.5 cm wide at the base, persistent, triangular, reddish brown, densely brown tomentose at emergence, glabrous at apex when mature, apex acuminate. Leaves 2-17, 46-216.5 cm long, descending, light green or brown, glaucous at emergence with whitish gray trichomes, glabrous at maturity. Petiole 23.3-111.5 cm long, terete, linear, pink at emergence, yellowish green green at mature leaves; unarmed to armed with 3-27 thin prickles 0.08-0.15 cm long. Rachis 17.6-114.5 cm long, terete, linear, pink at emergence, yellowish green at mature leaves, generally unarmed. Leaflets 6-17 pairs, opposite to subopposite, insertion in one plane, oblong to oblanceolate, longitudinally curved abaxially to planar, generally basally falcate, coriaceous, flat, green with adaxial and/or abaxial side glaucous, distal end with entire margins, acuminate (rarely acute) and asymmetrical (rarely symmetrical in apical leaflets) at the apex, attenuate at base, with conspicuous and light-green veins; median leaflets 22-37 × 3.9-5.6 (7) cm, 4.6-11.1 cm between leaflets; articulations 0.5-1.5 cm wide, green and yellowish. Pollen strobili solitary (up to 2), 10.8-25 cm long, 2.8-4.3 cm in diameter, cylindrical, erect, green with blackish trichomes at emergence, yellow-cream with blackish trichomes at maturity; peduncle 5-13 cm long, 1.5-1.8 cm in diameter, tomentose, light brown; microsporophylls 0.9-1.4 × 0.7-0.9 cm, discoid with a non-recurved distal face and a deeply lobate fertile portion, infertile portion 0.35-0.40 cm long and linear with straight horns 0.30-0.45 cm long, 0.73-0.80 cm and an acute angle between the horns. Ovulate strobili 15-26 cm long, 7.5-9.5 cm in diameter, solitary, cylindrical, erect, green with reddish brown trichomes at emergence, green with brown to blackish trichomes at maturity, acute apex; peduncle 5-18.5 cm long, 1.6-2 cm in diameter, pendulous and erect, tomentose, light brown; megasporophylls 30-56, 6-8 orthostichies with 5-7 sporophylls per orthostichy, 1.5-2.0 × 3.5-4.0 cm, with a prominent distal face, horns curved to straight and 0.70-0.90 cm long, 0.92-1.56 cm between horns with a right angle between the horns. Seeds 2-2.8 cm long, 1.8-2 cm in diameter, ovate, sarcotesta whitish pink at emergence, light brown at maturity.

Distribution and habitat.

Ceratozamia zoquorum is endemic to the northern mountains of Chiapas, Mexico (Fig. 29D ), where it occurs on karstic outcrops in evergreen tropical forest and oak forest between 500 and 1,150 m.

Etymology.

The specific epithet was established in honor of the Zoque culture ( Pérez-Farrera et al. 2001).

Common names.

None recorded.

Uses.

None recorded.

Conservation status.

( IUCN 2021). Ceratozamia zoquorum is listed as "Critically Endangered" under criteria A2c+4c; B1ab(i,ii,iii,v).

Discussion.

Ceratozamia zoquorum has oblong and coriaceous leaflets and leaves with scarce thin and short prickles. It belongs to a cryptic taxonomic group, and is geographically close to populations of C. becerrae and C. santillanii , the other two species in this group. The three taxa are distinguishable with the nrITS ( Martínez-Domínguez et al. 2017c). Morphologically, C. zoquorum differs from C. santillanii by its peduncle of ovulate strobili more than 3 cm long.

Specimens examined.

Mexico. Chiapas: Mun. Solosuchiapa , 530 m, 23 Jan 2014, F. Nicolalde-Morejón et al. 1931, 1932 (CIB); 550 m, 23 Jan 2014, F. Nicolalde-Morejón et al. 1933-1935 (CIB); 682 m, 24 Jan 2014, F. Nicolalde-Morejón et al. 1936-1947 (CIB); 531 m, 23 Jan 2014, L. Martínez-Domínguez et al. 1-5 (CIB); 500 m, 23 Jan 2014, L. Martínez-Domínguez et al. 6-14 (CIB); 682 m, 23 Jan 2014, L. Martínez-Domínguez et al. 15-34 (CIB); 520 m, 17 Apr 1996, M.A. Pe ́rez-Farrera 905 ( CH, CHIP, HEM) ; 520 m, 16 Apr 1996, M.A. Pérez-Farrera s/n (HEM); 19 Jan 2001, S. Avendaño 5216 (MEXU); 531 m, 20 Jan 2001, T.W. Walters 2001-2028-A (XAL). Mun. Tila, 1,135 m, 16 Jul 2021, F. Nicolalde-Morejón et al. 3698-3702 (CIB); 1,135 m, 16 Jul 2021, L. Martínez-Domínguez et al. 2326-2330 (CIB).

Figures

Figure 1. Characters evaluated in reproductive structures A pollen strobilus of Ceratozamia sabatoi B pollen strobilus of C. santillanii C ovulate strobilus of C. aurantiaca D ovulate strobilus of C. zoquorum.

Figure 23. Vegetative comparison between Ceratozamia zoquorum (A-C) and C. sancheziae (D-F). A juvenile plant B mature leaf C detail of leaflets and rachis D juvenile plant E, F leaves at emergence of adult plants.

Figure 29. Distribution of Ceratozamia species A C. vovidesii B C. whitelockiana C C. zaragozae D C. zoquorum.