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| Tridimeris huatuscoana Marinero-Sobal & Ortiz-Rodr., in Rodríguez & Marinero-Sobal, 2022. |
Abstract
Tridimeris is the only genus of Annonaceae endemic to Mexico. Despite this, the genus has been largely ignored and very little is known about it; specifically its diversity and distribution in Mexico are not well studied. Here a new species of Tridimeris, T. huatuscoana, is described and illustrated. The most general characteristics of the new species confirm that dimerous flowers (two sepals and four petals) and the large, and fleshy fruits are the most obvious synapomorphies for the Mexican genus Tridimeris. With respect to the other two species described so far (Tridimeris hahniana and T. chiapensis), the new species can be easily distinguished by the unique combination of 2-flowered inflorescences, large petals pubescent outside, food bodies present at the base of its inner petals, setose leaf domatia, and fruits shortly pedunculate and stipitate. The new species expands the richness of the genus to three species, all endemic to Mexico and restricted to montane cloud forests.
Keywords: dimerous flowers, Huatusco, Miliuseae, morphology, Neotropical
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| Tridimeris huatuscoana. A) Habit. B) Branchlet with inflorescences. C) Dimerous flower, note the white triangular patch at base of inner petals (food bodies). D) Monocarps. (Photographs by Esteban Marinero-Sobal). |
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| Tridimeris huatuscoana. E) Branchlet with inflorescences, note the color of the flowers and the pollination chamber. G) Close-up of the flower, note the two carpels surrounded by numerous stamens. H) Small plant of Tridimeris huatuscoana. (Photographs by Esteban Marinero-Sobal). |
Tridimeris huatuscoana Marinero-Sobal & Ortiz-Rodr. sp. nov.
Similar to Tridimeris chiapensis in its glabrous fruit surface and flowers with food bodies at the base of the inner petals, but differing from this species by its setose leaf domatia, longer and pubescent cream-white petals, greater number of flowers per inflorescence, fewer carpels per flower, and by its shorter pedicels.
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| Distribution range of Tridimeris huatuscoana (black star), Tridimeris hahniana (blue squares) and Tridimeris chiapensis (purple dots). |
Etymology:— The specific epithet is in honor of the municipality of Huatusco, in Veracruz, Mexico, one of the most important regions for coffee production, full of history and culture, and an obligatory path for many botanical explorers.
Andrés Ernesto Ortiz Rodríguez and Esteban José Marinero-Sobal. 2022. Fog and Coffee: A New Species of Tridimeris (Annonaceae) endemic to the Mountain Cloud Forest of Mexico. Phytotaxa. 548(2); 146-152. DOI: 10.11646/phytotaxa.548.2.2
