Ceratozamia sancheziae Perez-Farr ., Gut.Ortega & Vovides, Phytotaxa 500 (3): 209. 2021

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

28. Ceratozamia sancheziae Perez-Farr., Gut.Ortega & Vovides, Phytotaxa 500 (3): 209. 2021

Figs 9A , 12A , 23 D-F

Type.

Mexico. Chiapas: Mun. Tenejapa, 1,500 m, 16 May 2017, M.A. Pe ́rez Farrera 3558 ♀ (holotype: HEM [n.v.]; isotypes: MEXU [n.v.], XAL [n.v.]) .

Description.

Stem 8-30 cm long, 10-20 cm in diameter, semi-hypogeous, erect. Cataphylls 2.5-5.8 × 1.3-5 cm wide at the base, persistent, triangular, reddish brown, densely brown tomentose at emergence, glabrous at maturity, apex acuminate. Leaves 4-12 (20), 100-232.5 cm long, descending, green or brown at emergence with whitish gray trichomes, glabrous at maturity. Petiole 40-134.5 cm long, terete, linear, greenish brown or green in mature leaves; unarmed or with prickles 2-28 thin, 0.05-0.34 cm long. Rachis 55-120 cm long, terete, linear, brown or green in mature leaves, unarmed or with scarce prickles. Leaflets 20-35 pairs, opposite to subopposite, insertion in one plane, linear, in general longitudinally planar, not basally falcate (sometimes basally falcate), papyraceous, flat, green with adaxial side glabrous and abaxial side glaucous, distal end with entire margins, acuminate and symmetrical at the apex, attenuate at base, with conspicuous and green-light veins; median leaflets 22-36 × 1.7-3.0 cm, 1.4-3.5 cm between leaflets; articulations 0.55-1.1 cm wide, green. Pollen strobili 15-20 cm long, 1.8-3.2 cm in diameter, solitary, cylindrical, erect, light green at emergence, green with blackish trichomes at maturity; peduncle 6-10 cm long, 0.7-1.5 cm in diameter, tomentose, reddish brown to brown; microsporophylls 0.88-1.2 × 0.65-0.80 cm, discoid with a non-recurved distal face and a lobate fertile portion, infertile portion 0.32-0.40 cm long and rounded with straight horns 0.10-0.20 cm long, 0.63-0.70 cm and an acute angle between the horns. Ovulate strobili 12-25 cm long, 7.0-8.5 cm in diameter, solitary, cylindrical, erect, yellowish green at emergence, green with scarce blackish trichomes at maturity, acuminate apex; peduncle 5.0-11 cm long, 0.9-1.1 cm in diameter, erect, tomentose, brown; megasporophylls 35-100, 7-10 orthostichies with 5-10 sporophylls per orthostichy, 0.9-1.2 × 3.5-4 cm, with a prominent distal face, horns curved to straight and 0.50-0.73 cm long, 1.2-1.4 cm between horns with a right angle between the horns. Seeds 1.9-2.3 cm long, 1.4-1.5 cm in diameter, globose, sarcotesta whitish yellow when immature, light brown at maturity.

Distribution and habitat.

Ceratozamia sancheziae is endemic to Chiapas State, Mexico (Fig. 22D ), where it occurs in oak forest and pine-oak forest between 1,000-1,536 m.

Etymology.

This species was named in honor of María Ydelia Sánchez-Tinoco, for contributions to our knowledge of the anatomy of Mexican cycad seeds ( Gutiérrez-Ortega et al. 2021).

Common names.

None recorded.

Uses.

The community in Tenejapa use the leaves of this species for ornaments in traditional community festivities.

Preliminary conservation status.

Ceratozamia sancheziae could be included as “Endangered” (EN) in the IUCN Red List of Threatened Species based on the number of populations, which have between 70 to 250 adult plants.

Discussion.

Ceratozamia sancheziae is geographically close to C. robusta , but differs from it by its linear leaflets, leaves at emergence that are light green or reddish brown with a glaucous appearance, and ovulate strobili with curved to straight horns up to 0.73 cm long.

Here, we have recircumscribed and clarified the taxonomic identity of Ceratozamia sancheziae . In the description of this species, the authors mentioned Petalcingo as a municipality, but this is a locality that corresponds to Tila municipality in Chiapas (c.f. Gutiérrez-Ortega et al. 2021). The distribution range for this species was considered to extend from Tenajapa municipality in Chiapas to the mountain area close to the border with the State of Tabasco ( Gutiérrez-Ortega et al. 2021). However, we found specimens from Yajalón of Chiapas (M.A. Pérez Farrera 1635 from XAL) that do not correspond to the species description (Suppl. material 2). We carried out fieldwork and collected botanical material at the population level in the surroundings of Yajalón, Tila, Altamirano and Tenejapa. Based on the revision of herbarium specimens and the botanical material collected by us, we recircumscribed the populations for Ceratozamia in this region into two species: C. sancheziae and C. zoquorum . One diagnostic character for C. sancheziae is oblanceolate leaflets when juvenile, but we found in the field juveniles with linear leaflets only ( Gutiérrez-Ortega et al. 2021: 2009; Fig. 23D ). Furthermore, we did not find populations near Yajalón or Tila that correspond to C. sancheziae . The paratypes cited from Yajalón ( Méndez Ton 5498, 5722 both MEXU) have some vegetative characters that do not correspond with the species description; however, these could be part of the overall species variation of C. sancheziae . Considering that sympatry is possible in this genus and that there is broad variation in C. zoquorum , research at population level with reproductive structures and molecular variation could clarify what species is represented by these plants collected near Yajalón. In addition, we have extended the range for C. sancheziae to the south of Chiapas (i.e., populations from Altamirano municipality).

Specimens examined.

Mexico. Chiapas: Mun. Altamirano , 1,215 m, 16 Jul 2021, F. Nicolalde-Morejón et al. 3691-3697 (CIB); 1,215 m, 16 Jul 2021, L. Martínez-Domínguez 2318-2325 (CIB); 1,210 m, 28 Nov 1996, M.A. Pérez-Farrera 1468 (CHIP); 1,200 m, 18 May 1993, M. González-Espinosa et al., 1973 ( CH) . Mun. Tenejapa, 1,000 m, 5 Jun 1972, D.E. Breedlove 25506 (MEXU); 1,536 m, 15 Jul 2021, F. Nicolalde-Morejón et al. 3683-3690 (CIB); 1,536 m, 15 Jul 2021, L. Martínez-Domínguez et al. 2310-2317 (CIB). Mun. Yajalón, 1,434 m, 26 Aug 2015, F. Hernández-Najarro 4382 (CHIP).

Figures

Figure 9. Color of leaves at emergence A Ceratozamia sancheziae B C. kuesteriana C C. fuscoviridis D C. miqueliana.

Figure 12. Seeds of Ceratozamia A C. sancheziae B C. alvarezii C C. brevifrons. D C. subroseophylla.

Figure 22. Distribution of Ceratozamia species. A C. osbornei B C. robusta C C. sabatoi D C. sancheziae.

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.