Ceratozamia reesii Vovides, Perez-Farrera and Gutierrez-Ortega 2022, sp. nov.
Creators: name: Vovides, Andrew P.
name: Pérez-Farrera, Miguel Angel
name: Salinasrodríguez, María Magdalena
name: Galicia, Sonia
name: Díaz-Jiménez, Pedro
name: Calonje, Michael
name: Gutiérrez-Ortega, José Said
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Cycadopsida
Cycadales
Zamiaceae
Ceratozamia
Ceratozamia reesii

description: Ceratozamia reesii Vovides, Pérez-Farrera and Gutiérrez-Ortega sp. nov. (Fig. 14–17)
Ceratozamia reesii can be distinguished from other species in the genus by having 4–12 leaves per crown, light green color in emerging leaves, petioles armed with thin prickles, leaflets coriaceous, elliptic to lanceolate or oblanceolate, 11–23 pairs. Megastrobilus solitary erect, brown, peduncle 4.2–6 cm long. Seed 2–2.8 cm long.
Holotype. MEXICO, San Luis Potosí: Xilitla, Camino a San Pedro Huiztquilico, 790 m a.s.l., 31 July 2021, M.A. Pérez-Farrera, P. Díaz, & M.M. Salinas 4017 ♀ (HEM). Isotype: XAL.
Plant rupicolous, unbranching, stem short, cylindrical, erect, covered with persistent leaf bases, 12–33 cm tall, 10.5–17 cm in diameter. Cataphylls persistent, brown and densely tomentose at emergence, triangular apex acuminate. Leaves pinnate, 4–12 per crown, forming a semi-open crown, erect, ascending, olive green, 69.5–201 cm long, 39.6–71 cm wide, light green color at emergence, turning olive green at maturity. Petiole terete, 34–67.8 cm long, armed with thin prickles. Rachis green, terete, 34.5–138 cm long, erect, with sparse prickles diminishing into the distal end of the rachis. Leaflets 11–23 pairs, linear, long oblanceolate or oblanceolate, coriaceous, alternate to sub-alternate in the basal part of the leaf, subopposite in the median part, opposite in the apical part, subfalcate into apical part of leaflet, margin entire, apex acute to acuminate, asymmetric; base broad attenuate, articulation yellow adaxially, light green abaxially, 0.4–1.3 cm wide, veins 28–37, parallel, inconspicuous; median leaflets 19.8–35.5 cm long, 1.5– 5.1 cm wide, spaced 1.2–7.2 cm between leaflets. Microstrobilus solitary, conical, erect, light brown when mature, 33–35 cm long, 4.8–5 cm diameter, peduncle densely tomentose, light brown, 14–15 cm long, 1.5–1.8 cm diameter. Microsporophyll cuneiform, 10.11–12.59 mm long, 4.69–6.25 mm wide, distal face bicornate, with light brown color at the central portion, sporangia zone on abaxial surface 4.10–7.65 mm long, microsporangia grouped in 3–4 per sorus. Megastrobilus solitary, cylindrical, erect, 16–16.3 cm long, 6.5–8 cm diameter; apex mucronate, brown pubescent at mature, peduncle short, brown, tomentose, 4.2–6 cm long, 1.06–1.56 cm in diameter. Megasporophylls peltate, bicornate, 3.7–4.2 cm wide, 1.5–2.1 cm tall, distal face pubescent, when mature, distal face presents a light brown to brown color at the central portion, which fades to brown-reddish towards the margins. Seed ovoid, sarcotesta cream when immature, sclerotesta beige when mature, 1.45–1.67 cm diameter, 2.0– 2.28 cm long, with micropylar ridges.
Specimens examined: MEXICO. San Luis Potosí: Xilitla, Las Pozas, Jardín Escultórico Edward James, 665 m, 24 April 2018, M.A. Pérez-Farrera 4021 (HEM); Xilitla, El Cañón, 580 m, 30 July 2021, M.A. Pérez-Farrera, P. Díaz, & M.M. Salinas 4016 (HEM); Xilitla, Cerro de la Silleta, 1300 m, 20 July 2021, M.M. Salinas s.n. (QMEX); Cultivated at Jardín Botánico Francisco Javier Clavijero (Veracruz), accession 2001-110A, originally collected by S. Avendaño 5304 at Cerro del Muerto, Xilitla, 25 August 2014, A.P. Vovides 1522 (XAL).
Etymology: The specific epithet was chosen to honor the memory of John David Rees (1932–2021), an American botanist and a mentor on cycads to the principal author. His guidance and knowledge on Mexican cycads were invaluable to the later creation of the Mexican National Cycad Collection of the Francisco Javier Clavijero Botanic Garden of INECOL, Xalapa, Veracruz.
description: Published as part of Vovides, Andrew P., Pérez-Farrera, Miguel Angel, Salinasrodríguez, María Magdalena, Galicia, Sonia, Díaz-Jiménez, Pedro, Calonje, Michael & Gutiérrez-Ortega, José Said, 2022, Morphological and anatomical analyses clarify the species definition of Ceratozamia latifolia Miq. (Zamiaceae) and lead to the description of a new species: Ceratozamia reesii, pp. 224-252 in Phytotaxa 575 (3) on page 241, DOI: 10.11646/phytotaxa.575.3.2, http://zenodo.org/record/7431194