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| Begonia ostulensis Martínez & Ramos, in Martínez-Gordillo & Ramos-Ordóñez, 2022. |
Abstract
Begonia ostulensis sp. nov. is a new species from section Knesebeckia, known solely from the state of Michoacán; it is similar to Begonia monophylla, an endemic species from Mexico with a distribution in the states of Mexico, Colima, Michoacán, Guerrero and Morelos, but B. ostulensis differs from it in having an orbicular, peltate, solitary leaf, with the lower and upper surfaces glabrous, a lobed and double-dentate, non-ciliate margin, inflorescences terminal, peduncle and rachis glabrous and fruit with primary wing asymmetrically triangular, glabrous.
Keywords: Aquila, Cucurbitales, deciduous tropical forest
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| Begonia ostulensis in its habitat. Photographs by D. López-Guerrero. |
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| Begonia ostulensis Martínez & Ramos, A: Habit. B, B’: Pistillate flower (face and side views). C, C’: Staminate flower (face and side view). D: Ovary. E: Styles and stigmas. F: Cross section of the ovary. G: Fruit. H: Androecium. I: Stamen. J: Seed. K: Bract. L: Trichome ring. M: Tuber. Based on live plants in Santa María Ostula, by D. López-Guerrero and M.F. Ramos-Ordoñez. |
Begonia ostulensis Martínez & Ramos sp. nov.
§ Knesebeckia
Similar to B. monophylla Pav. ex A.DC. (1859:121), but differs in having orbicular, peltate leaves (vs. suborbicular to elliptic reniform or broadly ovate, basifixed leaves with a cordate base), that are glabrous on the lower and upper surfaces (vs. sparsely pubescent), with a lobed, double-dentate, non-ciliate margin (vs. with incised-dentate, ciliate margin, occasionally lobed); stipules fugacious (vs. persistent); inflorescence terminal (vs. axillary).
Etymology:—The name honors the type locality: Santa María Ostula, Aquila Municipality, Michoacan State, Mexico.
Distribution and habitat:—The species is only known from the type locality, on limestone rock ridges. Due to its size it is an inconspicuous species. It grows in cracks or lateral cavities of rocks (Fig. 2), never on the surface exposed to the sun, which makes it difficult to collect the tubers. Its life cycle is constrained by the rainy season (June to October); the leaf is observed in the first week of July, flowering occurs from July to September, in the month of November no flowers are found, only senescent leaves with dry fruits are observed. The type of vegetation is tropical deciduous forest, at elevations ranging from 604 to 828 m above sea level. It has been found in sites inhabited by Beiselia mexicana Forman (Burseraceae), another species endemic to the municipality of Aquila.
Martha Martínez-Gordillo and María Felix Ramos-Ordóñez. 2022. Begonia ostulensis (Begoniaceae), A New Species from Michoacán, Mexico. Phytotaxa. 543(1); 89–94. DOI: 10.11646/phytotaxa.543.1.9
