Ceratozamia santillanii Pérez-Farr. & Vovides, Syst. Biodivers. 7 (4): 435. 2009

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

29. Ceratozamia santillanii Pérez-Farr. & Vovides, Syst. Biodivers. 7 (4): 435. 2009

Figs 1B , 27E

Type.

Mexico. Chiapas: Mun. Berriozábal, road Berrioza ́bal-El Cairo , 15 Oct 2004, M.A. Pe ́rez Farrera 3030 ♀ (holotype: HEM! [HEM020981]; isotypes: XAL! [XAL0005415], MEXU [n.v.]) .

Description.

Stem 10-50 cm long, 11-13 cm in diameter, semi-hypogeous, erect and decumbent. Cataphylls 2-4.5 × 1.7-4 cm wide at the base, persistent, triangular, reddish brown, densely brown tomentose at emergence, with apex partiality glabrous at maturity, apex acuminate. Leaves 2-3, 50.5-79.3 cm long, descending, light green and glaucous at emergence, with whitish gray trichomes, green and glabrous at maturity. Petiole 23.5-45 cm long, terete, linear, yellowish green green in mature leaves; with 4-15 thin prickles, 0.05-0.15 cm long or unarmed. Rachis 23-40 cm long, terete, linear, yellowish green green at emergence, yellowish green in mature leaves, unarmed to armed with prickles. Leaflets 6-12 pairs, opposite to subopposite, insertion in one plane, oblong, longitudinally curved abaxially to planar, not basally falcate to basally falcate, coriaceous, flat, green with adaxial and abaxial sides glaucous, distal end with entire margins, acuminate and asymmetrical at the apex, attenuate at base, with conspicuous and green-light veins; median leaflets 17.4-30.6 × 4.2-6.5 cm, 3.5-7.1cm between leaflets; articulations 0.7-1.1 cm wide, yellow. Pollen strobili 15-20 cm long, 1.5-3.0 cm in diameter, solitary, cylindrical, erect, green with blackish trichomes at emergence, yellow-cream with blackish at maturity; peduncle 2-4 cm long, 1.0-1.3 cm in diameter, scarce pubescent, reddish brown to brown; microsporophylls 1.2-2 × 0.5-1 cm, discoid with a non-recurved distal face and a lobate fertile portion, infertile portion 0.34-0.37 cm long and linear with straight horns 0.20-0.25 cm long, 0.50-0.65 cm and an acute angle between the horns. Ovulate strobili 12-20 cm long, 7-9 cm in diameter, solitary, cylindrical, erect, green with blackish trichomes at emergence, green with scarce blackish trichomes at maturity, acute apex; peduncle 2-3 cm long, 0.9-1.3 cm in diameter, erect, tomentose, light brown; megasporophylls 21-56, 7-8 orthostichies with 3-7 sporophylls per orthostichy, 1.3-2.2 × 1.5-2.2 cm, with a prominent distal face, horns straight and 0.60-0.80 cm long, 1.65-1.90 cm between horns with an acute angle between the horns. Seeds 2.2-2.4 cm long, 1.8-2.0 cm in diameter, ovate, sarcotesta whitish pink when immature, light brown at maturity.

Distribution and habitat.

Ceratozamia santillanii is endemic to the northern highlands of Chiapas State, Mexico and only known from the type locality in the municipality of Berriozábal (Fig. 24A ), where it was collected in evergreen tropical rain forest on karstic rocks at 800-900 m.

Etymology.

The specific epithet was assigned in honor of Professor Trinidad Alemán Santillán in recognition of his academic accomplishments in the training of young biologists in botany and ecology ( Pérez-Farrera et al. 2009).

Common names.

None recorded.

Uses.

None recorded.

Preliminary conservation status.

According to IUCN criteria Ceratozamia santillanii should be listed as "Critically Endangered" (CR).

Discussion.

Ceratozamia santillanii belongs to a cryptic taxonomic group with C. zoquorum and C. becerrae , which is characterized by oblong and coriaceous leaflets with an acuminate and asymmetric apex. C. santillanii is easily distinguished from the other taxa in this complex with internal transcribed spacer region of nuclear ribosomal (nrITS) ( Martínez-Domínguez et al. 2017c), and peduncle of ovulate strobilus 3 cm long or shorter.

Specimens examined.

Mexico. Chiapas: Known only from the type locality. 15 Oct 2004, M.A. Pérez-Farrera 2944 (HEM) .

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 24. Distribution of Ceratozamia species. A C. santillanii B C. subroseophylla C C. tenuis D C. totonacorum.

Figure 27. Plants of Ceratozamia in habitat. A C. norstogii B C. oliversacksii C C. robusta D C. sabatoi E C. santillanii F C. tenuis G C. totonacorum H C. vovidesii I C. zaragozae.