Quetzalcoatlia glassii (Acev.-Rosas & Cházaro) A. Vázquez

Vázquez-García, J. Antonio, Basáñez, Miguel Cházaro, Acevedo-Rosas, Raúl, Rosales-Martínez, C. Santiago, Padilla-Lepe, Jesús, Martínez-González, Rosa E., García-Ruiz, Ignacio, Gutierrez, Byron Gutiérrez, Nieves-Hernández, Gregorio, Guzman, Ramón Cuevas, Shalisko, Viacheslav, Machuca-Núñez, J. Antonio, Hernández-López, Leticia & Muñiz-Castro, Miguel Á., 2025, Quetzalcoatlia (Crassulaceae), high small-scale diversification in western Mexico: a synopsis with four new species, Phytotaxa 695 (2), pp. 207-254 : 210-214

Quetzalcoatlia glassii (Acev.-Rosas & Cházaro) A. Vázquez & Rosales, Boletín Nakari 34(2): 39 (2023) ( Figs. 1–4 ).

≡ Graptopetalum glassii Acev.-Rosas & Cházaro, Novon 13(4): 378, Fig. 1 (2003).

Type:— MEXICO. Colima: municipality of Ixtlahuacán, carretera libre de Ixtlahuacán a Colima, justo enfrente del señalamiento del km 21 de la autopista Colima —Tecomán, sobre una pared de suelo yesoso con exposición NE, 410 m, 12 January 2000, R. Acevedo et al. 1724 (holotype XAL!, isotypes MO!, NY!).

Description:— Plants herbaceous, perennial, 16.0–20.0 cm tall, shortly caulescent or stemless, caespitose-ramose, forming compact clusters, branching by ascending (when young) and pendent (with age) slender stems from below rosette; stems 5.6–6.0 × 0.3–0.5 cm, mostly decumbent, suberect at first, then pendent, smooth, at first nearly white-glaucous, later red-brown-glaucous; rosettes 2.5–3.0 × 2.0–3.0(–4.0) cm, with 30–50 crowded leaves. Leaves 1.3–2.0 × 0.8–1.2 cm, 2.0–5.0 mm thick, oblanceolate to broadly oblanceolate, slightly concave on the inner surface, markedly convex on the outer surface and vaguely keeled in upper 2.0–4.0 mm, ascending-erect when young, later the apical ones ascending-erect and the basal ones expanding, glabrous, pale blue-greenish to white-greenish to yellow-green with palest rosy blush, especially in youngest leaves and with exposure to more intense light, slightly glaucous; apex acute or slightly apiculate, light green. Inflorescences as compound cymes, generally 6.0–12.0 cm, with 8–17 flowers, unbranched or with 1–2(–3) simple or bifurcate branches, each with 2–3 flowers, the basal branch with 1–2 flowers; peduncle 2.5–8.0 cm tall, 2.0– 3.5 mm thick, smooth, light green, pink or red-tinged; bracts 16–18, soon deciduous, 7.0–10.0 × 6.0–7.0 mm, 2.5 mm thick, similar to rosette leaves but ovate rather than oblanceolate, diminishing markedly

......continued on the next page in size, 7.0–10.0 × 6.0–7.0 mm; bracteoles mostly elliptic to lanceolate, 1.5–3.0 × 1.0– 1.5 mm; pedicels 0.6–0.7 cm; flower buds about 9.0 mm long. Flowers 8.0–9.0 mm long when unopened, 12.0–14.0 mm wide when expanded; calyx lobes 5, gray-green, lips 3.0 mm long; corolla tube 2.7–2.8 mm long, rotate in the distal half; corolla lobes 5.5–5.6 × 2.5–3.5 mm wide near base, triangular-lanceolate, acute, proximally yellowish green to yellow white and distally red and inconspicuously striped toward the tips, tin lips nearly solid red; nectaries 5, 0.3 mm tall, 0.5 mm wide, 0.3 mm thick, somewhat reniform, the inner face strongly concave, the external convex, yellow; stamens 5, 6.0–7.0 mm long, ca. 0.1 mm wide, antesepalous, at first erect, after anthesis strongly reflexed between the petals, base adnate to corolla tube, the filaments white, the apical half pink or red dotted, the anthers with gray-yellow pollen; gynoecium 6.0– 6.5 mm long, 3.0– 3.5 mm thick, obovate, carpels, rounded, proximally green-yellow to distally pinkish to reddish apically; styles 1.0 mm long or less. Fruits and seeds unknown.

Notes:— Quetzalcoatlia glassii differs from Q. pentandra in its shorter herbaceous habit, cespitose growth, smaller stems, rosettes, and leaves, and a shorter but thicker inflorescence ( Table 1). Quetzalcoatlia glassii can be recognized in the field among other known species of the genus by its small, attractive, light green and dense rosettes, its shorter and slender stems, and the numerous conglomerate leaves (30–50). Plants of Quetzalcoatlia glassii are sold as “ Graptopetalum sotoi ”, a nomen nudum, that was initially meant to be applied to this species ( Cházaro-Basáñez & Acevedo-Rosas 2008). Figure 4A depicts a cultivated plant, which is more branched and robust than wild plants. Table 1 outlines the key distinctions between Quetzalcoatlia glassii and all the species of the genus.

Distribution, habitat, and phenology:—Endemic to the state of Colima, at an elevation of 380–440 m, where the species occurs in tropical deciduous forests, on shaded gypsum slopes harboring a rich succulent flora including Agave colimana Gentry , A. pablocarrilloi A. Vázquez, Muñiz-Castro & Padilla-Lepe , Bursera schlechtendalii Engl. , Bursera spp , Ficus sp , Hechtia laevis L.B. Sm. , Matelea cyclophylla (Standl.) Woodson , Cephalocereus nudus E.Y. Dawson ; Euphorbia spp , Ficus cotinifolia Kunth , Pinguicula colimensis McVaugh & Mickel , Pittocaulon filare (McVaugh) H. Rob. & Brettell , Plumeria rubra L, Ceiba aesculifolia (Kunth) Britten & Baker f. and Pseudobombax ellipticum (Kunth) Dugand. Quetzalcoatlia glassii flowers from late February to April or June. Flowers produce a fetid odor.

Etymology:—The species is named after Charles Glass (1934–1998), who discovered and collected plants of the new taxon for the first time in the winter of 1995, during vacation time, on gypsum slopes halfway between Tecomán and Colima. Mr. Glass worked as the Curator of Plants for Cante, A.C. (a non-governmental organization), a small botanical garden located in San Miguel de Allende, Guanajuato, Mexico, where he studied succulent plants such as Cactaceae and Crassulaceae . Mr. Glass conducted many field trips to remote and interesting places in Mexico, where he found and described new taxa of these groups. Plants of this species are sold as “ Graptopetalum sotoi ”, a nomen nudum, because Miguel Cházaro and Charles Glass were planning to publish it.

Preliminary conservation assessment:—Following IUCN Red List criteria B1ab(iii) ( IUCN 2022), the species was assessed as Endangered (EN): the EOO is less than 5000 km 2 (criterion B1), the AOO is <500 km 2 (B2), its habitat is severely fragmented (condition a); and we inferred a decline in the quality of its habitat through land use change, from mining and agricultural expansion (condition b(iii)). The authors have observed that this species is reproduced in several private collections and sold in various nurseries.

Additional specimens examined:— MEXICO. Colima: Near La Salada , approx. 25 km S of Colima on a steep and shaded gypsum slope, 29 December 1995. C. Glass & M. Mendoza 8910 (Cante, A.C) ; Cultivated from collected material from La Salada, rocky, gypsum slope, southwest of Colima, approx. 25 km, old road to Tecomán. 3 August 1997, I. García 4610 ( CIMI!) ; La Salada, sur y oeste de Ixtlahuacán , Colima. 25 March 1999, I. García & Fco. J. Santana-Michel 5577 (CIMI!, ZEA!) ; La Salada, property owned by the cement mining company Holcim , 28 June 2014, R. Cuevas G., et al. 11276 ( ZEA!) .

Additional on-line observations:— I. Novoa-Leyva (ismael76) https://www.inaturalist.org/photos/102113659; P. González Zamora (pierre-glez) https://www.inaturalist.org/photos/112649177; jarturoq (jarturoq) https://www. inaturalist.org/photos/130159619; jarturoq (jarturoq) https://www.inaturalist.org/photos/130159518

Figures

FIGURE 1. Geographic distribution of species of Quetzalcoatlia. All species of Quetzalcoatlia within a radius equal to or less than 101 km.

FIGURE 2. High small-scale rosette diversity in Quetzalcoatlia, half of their actual size.A. Quetzalcoatlia trujilloi. B. Q. itzicuaroensis. C. Q. superba. D. Q. glassii. E. Q. kristenii. F. Q. rosanevadoensis. G. Q. latipetala. H. Q. grulloensis. I. Q. pentandra. J. Q. santamichelii. Photographs:A & D–E by J. Etter & M. Kristen, B–C & F by A. Vázquez-García, April 2022, G Reproduced from Kimnach (1987), H by J. Padilla-Lepe, I Reproduced from Moran (1971), J. by D. Figueroa-S.

FIGURE 3. Quetzalcoatlia. High small-scale flower diversity in western Mexico, size-proportions kept among the flowers. A. Quetzalcoatlia latipetala. B. Q. glassii. C. Q. pentandra. D. Q. itzicuaroensis. E. Q. superba. F. Q. grulloensis. G. Q. rosanevadoensis. H. Q. kristenii. I. Q. trujilloi. J. Q. santamichelii. Photographs: A by I. García Ruiz, B, D–E & G–I by J. Etter & M. Kristen, C reproduced from R. Moran (1971), F by J. Padilla-Lepe, and J by A. Vázquez-García.

FIGURE 4. Quetzalcoatlia glassii. Photographs by J. Etter & M. Kristen.