Quetzalcoatlia itzicuaroensis A.Vázquez, Padilla-Lepe & I. García, 2025

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 : 220-231

Quetzalcoatlia itzicuaroensis A.Vázquez, Padilla-Lepe & I. García sp. nov. ( Figs. 1–3 & 7–15 ).

Type:— MEXICO. Michoacán: municipality of Los Reyes, Chorros del Varal , 12.5 km SW of Los Reyes de Salgado (cultivated by Jesús Padilla-Lepe ), 13 April 2022 (fl & fr) J. Antonio Vázquez-García 10290 (holotype IBUG!; isotype CIMI!) .

Diagnosis:— Quetzalcoatlia itzicuaroensis is similar to Q. pentandra in rosette size and color pattern of the flowers but it differs from the latter in having a serpentine herbaceous pendant habit vs. erect (possibly decumbent) and suffruticose; much longer full-sized stems up to 48 vs. <15 cm; basal leaves up to 3.8 vs. up to 6.4 cm long, adaxial surface usually concave rarely flattish vs. usually flattish to convex, rarely slightly concave; leaf apex mostly acute vs. mostly obtuse or rounded or truncated; shorter inflorescences 12.9–16.4(–18) vs. 20.0–35.0 cm; more numerous branches per full-size inflorescence 4–7 (vs. 3); smaller corolla, 14.0–16.2 vs. 17.9–18.0 mm in diameter; shorter but wider petal segments, 5.9–6.1 × 3.0–3.4 vs. 6.9–7.0 × 1.7–1.75 mm; longer and wider corolla tube, 4.5–4.6 × 5.7 vs. 3.0–3.5 × 4.0 mm.

Description:— Plants herbaceous, perennial, 9.0–55.0 cm tall, caulescent, sinuously pendant, cespitose, glabrous; stems 6.0–48.0 × 0.3–0.6 cm, prostrate to sinuously pendant, smooth, brownish to green; leaf scars 1.6–2.5 × 1.1– 1.5, bumped, centrally whitish, the outline pinkish to brownish; rosettes terminal, 3.0–7.0 × 6.4–8.4 cm in diameter, compact, with 12–34 leaves. Leaves 1.9–2.9(–3.8) × 1.0– 1.5 cm, 2.0–3.0 mm thick at the base, mostly obovate, the basal ones obovate and up to 3.8 cm long; adaxially usually concave, rarely flattish and abaxially convex, keeled at mid vein; the margins entire and rounded; glabrous, glaucous greenish to grayish or pinkish, when green, the margins and or tips often pinkish; the base cuneate; the stalk-like, basal portion 3–4 mm wide; the apex mostly acute, rarely obtuse or rounded or truncated; apical mucro 1.5–2.0 × 1.5–1.6 mm. Inflorescences 1–3(–4), shorter than wider, 12.9–16.4(–18) × 18.0– 18.6 cm, 12–34 flowers on 4–7 secondary axes (branches), rarely opposite, each branch spaced 2.0–3.0 cm; primary axis 2.0– 3.5 mm thick at the base, 1.0– 1.5 mm thick above, straight, bluish-gray to pinkish; basal bracts on primary axis deciduous, 4–9, 7.0–9.0 × 4.0–6.0 mm, lenticular, lanceolate, gray; branches 5.6–9.7 × 1.1–1.2 mm, zigzagged, with 2–14 flowers, with 2–8 flowers on basal branches, with each pedicel spaced 8.0– 16.1 mm, bracteoles 3–7, 1.1–2.1 × 2.0– 2.1 mm, narrowly ovoid, glaucous-grayish; pedicels 1.0–2.0 × 0.11–0.12 cm, glaucous grayish; flower buds 6.4 × 5.3 mm, ovoid, the sepal lobes glaucous greenish, the corolla penta-costate with each petal keeled, glaucous yellowish, glabrous. Flowers 14.0– 16.2 mm in diameter; calyx fused 1.4–1.5 × 2.6–2.7 mm; calyx lobes 2.4–2.5 × 0.9–1.3 mm; corolla tube 4.5–4.6 × 5.7 mm; corolla lobes 5.9–6.1 × 3.0– 3.4 mm, triangular, subequal, longitudinally shallowly furrowed, proximally greenish, the base of corolla lobes sparsely dark red spotted, distally with transverse v-shaped red stripes or solid dark-red on upper ½–⅔; nectaries 0.8 × 0.9 mm, the apex rounded, bright yellow; stamens 5, erect at early stage of anthesis, later reflexed, red to pink; filaments 6.8–6.9 × 0.1–0.7 mm, the base mostly with short red lines, distally dark red, whitish to pale green below; anthers 0.4 × 0.3 mm, broadly ovoid, beige; gynoecium 4.0 × 4.1 mm, mostly the lower half yellowish to whitish, the distal 5–10% pinkish, the style purplish; carpels 6.1–6.3 × 1.0– 1.3 mm, cylindroid and acuminate, abaxially obtuse to rounded, yellow to distally pinkish; styles 1.1–1.2 × 0.1–0.5 mm long; stigmas 0.3–0.4 mm. Fruits 4.9–5.6 × 1.2–1.5 mm, oblongoid, costate; carpels obtuse, proximally yellowish to distally pinkish; seeds 0.37–0.49 × 0.09–0.17 mm long, yellowish brown.

Distribution, habitat, and phenology:— Quetzalcoatlia itzicuaroensis is known only from some subpopulations at the type locality, in Los Reyes municipality, in the Michoacán state. It is located in the middle part of the Tepalcatepec river basin, at an elevation that ranges between 800–1000 m.The vegetation is tropical deciduous and semideciduous forest, growing on rocky slopes shaded in the north aspect, together with Agave garciaruizii A.Vázquez, Hernández-Vera & Padilla-Lepe , Anthurium halmoorei Croat , Astrolepis sinuata (Lag. ex Sw.) D.M. Benham & Windham , Euphorbia sp. , Hechtia purhepecha I. García, Espejo & López-Ferr. and Tillandsia capitata Griseb. ( García-Ruiz et al. 2014, García-Ruiz & Lott 2015, Hernández-Vera et al. 2019). It flowers in early March to April, fruiting from May to June.

Etymology:—The specific epithet refers to the name of the location of this species, at the Itzícuaro river canyon, where the spectacular waterfalls Chorros del Varal are located, at Los Reyes, Michoacán.

Notes: —In 1990, the species was first collected at Chorros del Varal by Ignacio García Ruiz. Miguel Cházaro revisited the area and thought that it was the second wild location of Graptopetalum pentandrum . Despite its great variability, a close comparison allowed us to conclude that the populations of this locality should be described as a new species. This species is often sold at nurseries as Graptopetalum pentandrum .

Preliminary conservation assessment:—Following IUCN Red List criteria B1ab(iii) ( IUCN 2022) the species was assessed as Critically Endangered: the EOO is less than 100 km 2 (criterion B1); AOO <10 km 2 (B2); only known from a single location (condition a); and an inferred decline of quality of habitat (condition b(iii)) through recreation and increasing water demands for irrigation. The species is propagated at University of Guadalajara-Zapopan.

Additional specimens examined:— MEXICO. Michoacán: Los Reyes municipality, Chorros del Varal , 26 April 1990, I. García et al. 3173 ( CIMI) ; same locality, in front of the falls, 5 April 1993, H. Díaz-Barriga 7384 ( IEB!) ; same location, Acevedo 1723 ( XAL!) ; same location, cultivated at Jiquilpan, the source from Chorros del Varal, Municipio de Los Reyes , Michoacán, 1550 m, 15 April 1996, I. García 3984 ( CIMI!) ; Barranca de Los Chorros del Varal, municipio de Los Reyes, Michoacán, río arriba del puente hacia El Salto , 900–940 m, 24 March 2004, I. García & A. Linares 6431 (CIMI!, IEB!) ; Barranca Chorros del Varal, hasta la parte más baja, municipio de Peribán , Michoacán, 820–850 m, 11 May 2004, I. García & A. Linares 6500 (CIMI!, IEB!) ; Barranca Chorros del Varal, municipio de Los Reyes-Peribán, Michoacán, 900–1000 m, 14 April 2005, I. García & H. Cortez 7065 (CIMI!, IEB!) ; Barranca Chorros del Varal, a orilla del río Apupátaro, municipio de Los Reyes , Michoacán, 900–1000 m, 06 April 2006, I. García 7433 (CIMI!, IEB!) ; 12.5 km al SW de Los Reyes de Salgado , 12 July 1998, P. Carrillo R. & M. Cházaro B. 319 ( IEB!) .

Quetzalcoatlia kristenii (Etter, A. Vázquez & Rosales ) A. Vázquez & Rosales, Boletín Nakari 34(2): 39 (2023) ( Figs. 1–3 & 16 ).

≡ Graptopetalum kristenii Etter, A. Vázquez & Rosales, Phytotaxa 555 (2): 140 (2022) .

Type:— MEXICO. Michoacán: municipality of Coalcomán, SW of San Acamitán, shady cliffs along Coalcomán river in tropical deciduous forest, 20 March 2013, J. Etter & M. Kristen 3764 (holotype IBUG!, isotype CIMI!).

Description:— Plants herbaceous, perennial, 8.0–30.0 cm tall without inflorescence, caulescent, pendant, cespitoseramose, sometimes forming dense groups, branching basally and from the leaf axils; stems 4.0–22.0 × 0.25–0.35 cm at the base, erect at first, later decumbent to pendant, surface smooth, green-brownish to grayish, pinkish to green-glaucous from a short segment below the rosette upwards; leaf scars prominent, 1.0– 1.5 mm in diam., circular, green-brownish, the tips grayish; rosettes terminal (2.3–)4.0–8.0 × (2.8–)3.5–5.0 cm, with somewhat scattered leaves but compact to the apex, with 15–30 leaves. Leaves 1.4–2.7(–3.2) × 0.7–1.3 cm, 4.0– 4.5 mm thick, the thickest part near the middle, broadly oblong, straight to sometimes incurved, shortly acuminate, greenish to glaucous-pinkish, sometimes with a different darker pinkish to purplish tonality toward the apex, somewhat pruinose, papillose; the margins entire, rounded; the base obtuse to truncate, the stalk-like, basal portion 12.0–13.0 mm wide; the apex acute, usually inclined upwards, adaxially slightly concave, abaxially convex; apical mucro 1.0–2.0 × 1–1.5 mm. Inflorescences as paniculate cymes, 18.0–28.0 × 10.0– 11.1 cm, the fertile portion 6–7 mm long; (10–)15–24 flowers on 2–4 primary branches; primary axis 2.5–3.5 mm thick at the base, 1.0– 1.2 mm thick above, gray-bluish to pinkish; bracts on primary axis 1.0–1.3 × 0.4–0.7 cm, those below the branches 0.2–0.4 × 0.1–0.2 cm, gradually smaller upwards to 0.4–0.7 × 0.2–0.4 cm; oblong-obovate or lanceolate to elliptic; the basal primary branches 2.0–6.0 cm, somewhat zig-zag shaped, the basal usually simple, with 1–4 flowers, the rest mostly bifurcate, with 1–7 flowers each; bracteoles 1.1–1.5 × 0.7–0.8 mm irregularly scattered, lanceolate to elliptic, obtuse at the base, acute at the apex, glabrous, grayish to pinkish; pedicels 0.6–1.1 ×.06– 0.1 cm, the same color as the primary axis or dark reddish; flower buds ovoid, obtuse at the base, acute at the apex, the corolla pentacostate, whitish to pinkish toward the apex, calyx reaching to ca. ⅓ of its length, glaucous green. Flowers 12.5–15.5 mm in diameter; calyx fused 0.5–0.6 × 2.7–3.6 mm; calyx lobes 1.5–1.8 × 1.3–1.4 mm, triangular, glaucous-greenish; corolla tube 2.4–2.9 × 4.1–4.5 mm; corolla lobes 5, subequal, 4.9–6.2 × 2.2–2.6 mm at the widest part (near the middle), triangular, shortly acuminate, bending back, white with conspicuous red stains along, with a shallow middle-groove along; proximally white-pinkish, to distally reddish-wine; nectaries 0.7 × 0.7 mm, bright yellow; stamens 5; erect at first, later curving outside, white-pinkish, filaments 3.9–4.1 × 0.1–0.4 mm, anthers ellipsoid 0.5–0.6 × 0.2–0.4 mm white or blackish; gynoecium 6.7–6.8 × 3.7–3.8 mm, protruding from the corolla 2.3 mm, creamish-yellow to yellow-greenish, obovate, carpels 5.0– 6.1 mm, abaxially obtuse to rounded, pale yellowish to pale greenish, the tips reddish; styles 1.3–1.4 × 0.3–0.4 mm long, reddish; stigmas 0.1–0.2 mm in diam., pale pink. Fruits 5.4–5.6 × 1.2–1.4 mm; seeds 0.41–0.49 × 0.15–0.18 mm.

Notes:— Quetzalcoatlia kristenii is similar to Q. itzicuaroensis , but it differs from the latter in rosette diameter, 3.4–5.0 cm vs. 6.0–8.0 cm; leaf broadly oblong vs. obovate; basal branch with fewer flowers than in the rest of branches vs. with an overlapping number of flowers concerning the rest of branches; flower diameter 12.5–13.5 vs. 17.0–19.0 mm; petal width 2.2–2.6 mm vs. 1.7–1.8 mm; petal widest part near the base vs. near the middle; and petal color pattern white with conspicuous red spots along vs. white to yellowish, with a rhomboid dark red spot in the upper half of the petal.

Distribution, habitat, and phenology:—So far, Quetzalcoatlia kristenii is known only from a single population in the Sierra de Coalcomán, Michoacán. It grows in tropical deciduous forest on rocky vertical slopes along a small portion of the Río Coalcomán, at an elevation between 700–800 m, with Agave andreae Sahagún & A. Vázquez , Anthurium halmoorei Croat , Philodendron warscewiczii K. Koch & C.D. Bouché , Bursera spp. , Epidendrum ciliare L., Oncidium leleui R. Jiménez & Soto-Arenas ; Mammillaria sp. , Opuntia sp. , Selenicereus murrillii Britton & Rose , Pittocaulon hintonii H. Rob. & Brettell , Pseudobombax sp. , and Tillandsia spp. The development of the inflorescence starts to be evident during the first two months of the year. The flower anthesis occurs between early March and early April, fruiting in May.

Etymology:—The specific epithet honors Martin Kristen, an outstanding explorer, horticulturist, and expert in succulent plants, whose work contributed to the discovery of some new species of Asparagaceae and Crassulaceae , including the one described here.

Preliminary conservation assessment:—We assessed the new species as Critically Endangered (CR) based on the IUCN Red List criteria B1ab(iii) ( IUCN 2022). The species is known from a single population (condition a) within an area of less than 10 km 2. The EOO is 10 km 2 (criterion B1) and the AOO is 4.0 km 2. There is a continuing decline observed in the extent and quality of its habitat (condition b(iii)). A population reduction is expected due to deforestation for agriculture and climate change, which could cause more severe natural disasters and alter the microclimate of this fragile habitat.

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 7. Quetzalcoatlia itzicuaroensis. Cultivated by J. Padilla-Lepe; Photograph by A. Vázquez-García, April 2022.

FIGURE 8. Quetzalcoatlia itzicuaroensis. Photographs: A by Omar Rentería (https://www.naturalista.mx/photos/175856162), January 2022, B–C by J. Padilla-Lepe, April 2022.

FIGURE 9. Quetzalcoatlia itzicuaroensis. Photographs: J. Padilla-Lepe, December.

FIGURE 10. Quetzalcoatlia itzicuaroensis. Photographs by R. Arredondo-T., May 2019: https://www.naturalista.mx/photos/: 33774644, 33774695, 33774702, 33774717, 33774740 & 33774745).

FIGURE 11. Quetzalcoatlia itzicuaroensis. Chorros del Varal waterfalls, S of Apupátaro river, © M. Costea, I. García-Ruiz & G. Costea, Feb. 2013 (www.phytoimages.siu.edu).

FIGURE 12. Quetzalcoatlia itzicuaroensis. Photographs by M. Cházaro-Basáñez, Nov. 1995.

FIGURE 13. Quetzalcoatlia itzicuaroensis. Photographs: J. Etter & M. Kristen (No. 919), Mar 2005.

FIGURE 14. Quetzalcoatlia itzicuaroensis. Photographs: J. Etter & M. Kristen (No. 919). Mar 2005.

FIGURE 15. Quetzalcoatlia itzicuaroensis. Photographs: J. Etter & M. Kristen (No. 1089).Apr. 2022.

FIGURE 16. Quetzalcoatlia kristenii (Pinzán, municipality of Coalcomán).A. Habit, rosettes and inflorescence. B, D. Flowers at anthesis. C. Leaf and flower variability. E. Rosettes. F. Section of inflorescence. G. Flower size. H. Leaf size. Photographs: J. Etter & M. Kristen, Mar. 2013.