Ceratozamia guatemalensis Pérez-Farrera, Gutiérrez-Ortega & Quezada, 2024

Pérez-Farrera, Miguel Angel, Díaz-Jiménez, Pedro, Quezada, Maura L., Marroquín-Tintí, Andrea, Delgado Montejo, Héctor M., Mendoza-Montejo, Sandy A. & Gutiérrez-Ortega, José Said, 2024, Ceratozamia guatemalensis (Zamiaceae): A new cycad species from Mesoamerica, Phytotaxa 668 (1), pp. 63-80 : 71-73

Ceratozamia guatemalensis Pérez-Farrera, Gutiérrez-Ortega & Quezada sp. nov. ( Figs. 10–15 ).

Type:— GUATEMALA. Huehuetenango, Sierra de los Cuchumatanes, 7 February 2020, M. Quezada & M. A. Pérez-Farrera 5826 ♂ (holotype HEM!, isotypes: USCG!, XAL!)

Diagnosis:— Ceratozamia guatemalensis is distinguished by having emerging leaves of light olive-green color that turn reddish-brown when immature, and then olive green when mature; slightly arching mature leaves; papyraceous, channeled leaflets; green leaflet articulations on the adaxial side; conspicuous veins on the abaxial surface; hypogeous trunk at maturity, although sometimes semiarborescent, erect or decumbent; erect, light green pollen cones; and pendent seed cone when mature.

Plant terrestrial, unbranching Stem short or medium, cylindrical, erect or rarely decumbent with age, covered with persistent leaf bases, 11–50 cm tall, 14–24 cm in diameter. Cataphylls persistent, brown and densely tomentose at emergence, triangular, apex acuminate. Leaves pinnate, 4–11 per crown, forming a closed crown, erect, ascending when young, descending when older, 161–212.1 cm long, 53.4–72.6 cm wide, green, glaucous, lightly tomentose at emergence, turning reddish to brown and finally olive-green at maturity. Eophylls six. Petiole terete, 52.5–131.2 cm long, armed with thin, long prickles. Rachis green, terete, 97–146.8 cm long, erect, with sparse prickles diminishing into the distal end. Leaflets 40–76 pairs, linear, long, slightly channeled or flat, papyraceous, alternate or subalternate basally, subopposite to alternate medially, opposite to subopposite apically, subfalcate basally and medially, margin entire, apex acute to acuminate, symmetric; base broad attenuate, articulation green adaxially, 0.61–0.98 cm wide, veins conspicuous abaxially, 12–18, parallel; median leaflets 26.7–47 cm long, 1.14–1.58 cm wide, spaced 0.6–1.67 cm apart. Microstrobilus solitary, conical, erect, light green when mature, 25–31 cm long, 4–4.4 cm diameter, peduncle densely tomentose, reddish, 12–14 cm long, 1.5–2.2 cm diameter. Microsporophyll cuneiform, 10.3–13.5 mm long, 8.7–11.2 mm wide, green, distal face bicornate, with dark reddish trichomes centrally, sporangia zone on abaxial surface only, 7.3–10.1 mm long, microsporangia grouped in 3–4 per sorus. Megastrobilus solitary, green, black tomentulous at maturity, cylindrical, pendent, 22.3–25 cm long, 6.18–6.5 cm diameter; apex apiculate; peduncle densely tomentose, light brown, 5–9.0 cm long, 1.4–1.5 cm in diameter. Megasporophylls peltate, bicornate, green, 3–3.6 cm wide, 1.8–2 cm tall, distal face pubescent black when mature, distal face presents black tomentulus on the edge and at the base of the horns. Seed ovoid, sarcotesta cream when immature, sclerotesta beige when mature, 2–2.3 cm long, 1.8–1.9 cm diameter, with micropylar ridges.

Habitat description:— This cycad is found in Cupressus-Pinus-Quercus forest, according to the classification of Breedlove (1981). Ceratozamia guatemalensis grows with Hesperocyparis lusitanica (Mill.) Bartel (2009:181) , Clusia guatemalensis Hemsl (1878:2) ., Pinus oocarpa Schiede (1838:491) , Quercus peduncularis Née (1801:270) , Quercus acutifolia Nee (1801: 267) , Quercus polymorpha Schltdl. & Cham. (1830: 78) and Liquidambar styraciflua L. (1753: 999). Plants grow in dark brown clay soil (60% soil loam, 20% sandy, 10% silt loam, 20% clay loam) with pH 4.5–5.5 ( García-Ortiz 2007) and generally on steep slopes of about 35°. The metamorphic rock fragments (Chiastolite phyllite and schist) and Fusulinid limestone are present in conglomerate, corresponding to Late Jurassic-Early Cretaceous age ( Clemons & Burkart 1971). The elevational range of the species is 900–1950 m a.s.l.

Etymology:— Ceratozamia guatemalensis is named for its country of endemicity.

Additional specimens examined:— GUATEMALA. Departamento de Huehuetenango, Sierra de los Cuchumatanes , 8 November 2023, M. G. Martinez-Martinez 134 ♀ ( HEM) ; Departamento de Huehuetenango, Sierra de los Cuchumatanes , 2 June 2022, M. A. Pérez-Farrera et al. 4259 ♂ ; M. Quezada et al. 5930 ♂ ( USCG; HEM) ; Departamento de Huehuetenango, Sierra de los Cuchumatanes , 27 April 2021, M. A. Pérez-Farrera, P. Díaz-Jiménez, A. Marroquín-Tintí 4003 ( USCG; HEM) ; Departamento de Huehuetenango, Sierra de los Cuchumatanes , 8 February 2020, M. A. Pérez-Farrera et al. 3870 ( USCG; HEM) ; Departamento de Huehuetenango, trail between Catarina and San Andrés, Sierra de los Cuchumatanes , 3 September 1942, J. A. Steyermark 51818 ♀ ( F; US) ; San Andrés , 30 May 1906, O. F. Cook 51 ( US) .

Figures

FIGURE 10. Stages of an immature adult plant leaf of Ceratozamia guatemalensis. (A) Leaf during emergence. (B) Growing emergent leaves. (C) The olive-green color gradually turns to reddish-brown upon before reaching maturation. (D) Mature leaf.

FIGURE 11. Morphology of leaves in Ceratozamia guatemalensis. (A) Seedling, (B) Juvenile. (C) Adult plant.

FIGURE 12. Ceratozamia guatemalensis plants in habitat.

FIGURE 13. Megastrobili (seed cones) of Ceratozamia guatemalensis. (A) Immature cones are erect. (B) Mature cones are pendent.

FIGURE 14. Holotype of Ceratozamia guatemalensis.

FIGURE 15. Reproductive structures of the holotype of Ceratozamia guatemalensis.