Mammillaria morentiniana
- Holotype: Mexico, San Luis Potosí, Santa María del Río, alt. 2056 m, 28 Aug 2019, P. González-Zamora 11 (IBUG: 215375)
- Isotype: Mexico, San Luis Potosí, Santa María del Río, alt. 2056 m, 28 Aug 2019, P. González-Zamora 11 (SLPM)
- 1. González-Zamora, P., Aquino, D., Mohl, J. & Sánchez, D. 2022: A new endemic species of Mammillaria (Cactaceae) from San Luis Potosí, Mexico. – Willdenowia 52(3): 359-372. http://doi.org/10.3372/wi.52.52305
Distribution (General)
Endemic to S San Luis Potosí, MexicoA
Diagnosis
Mammillaria morentiniana is distinguishable from M. bocasana, M. crinita and M. nana by the presence of more than 4 central spines (mean = 5), and differs from M. schwarzii, which presents, on average, 7 thinner central spines. Mammillaria morentiniana bears fewer than 32 straight radial spines (mean = 24.49), whereas M. schwarzii bears more than 32 straight radial spines (mean = 38.98). Mammillaria morentiniana has completely red central spines and black, non-arillate seeds, whereas M. bocasana has red central spines with a yellow base and reddish brown, arillate seeds. Mammillaria morentiniana has glabrous spines and straight radial spines, whereas M. crinita has pubescent spines and tortuous or straight radial spines. Mammillaria morentiniana differs from the sympatric M. nana because the latter has tuberous roots and 0 or 1 pubescent central spines.A
Description
Roots slender branched. Stem simple to branched, 2.2–4(–6) cm tall, 1.5–2.6 cm in diam., growth form globose to shortly cylindric, latex watery; tubercles 2–3.5 mm long, 1.5–2.5 mm in diam., axils with tortuous bristles; areoles circular, 0.6–1 mm wide; central spines (3 or)4–6(–8), reddish, acicular, (3.7–)5–8(–9.4) mm long, glabrous, 1 or 2 of them uncinate; radial spines (17–)19–28(–32), white, acicular, (0.4–)0.5–0.7(–9.2) mm long, glabrous. Flowers infundibuliform, 7–9 mm long; outer tepals pale yellow with reddish middle stripe, lanceolate, margin entire; inner tepals pale yellow, lanceolate, margin entire; filaments pale yellow; anthers yellow; style pale yellow; stigma pale yellow, 4-lobed. Fruit pink, claviform, 10–20 mm long; seeds black, c. 1.1 mm in diam.; aril absent; testa pitted.A
Bibliography
A. González-Zamora, P., Aquino, D., Mohl, J. & Sánchez, D. 2022: A new endemic species of Mammillaria (Cactaceae) from San Luis Potosí, Mexico. – Willdenowia 52(3): 359-372. http://doi.org/10.3372/wi.52.52305