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Erythroxylum macrophyllum is a morphologically variable and widely distributed species complex in Central and South America with several sub-specific taxa and numerous species included in its synonymy. A single variety grows in the Colombo-Venezuelan savanna region which can be distinguished from the rest of the E. macrophyllum complex by the size of leaves, cataphyll and stipule characteristics, and shape of calyx lobes. A molecular phylogeny reconstructed from 519 nuclear genes also reveals that the savanna variety is more closely related to E. acuminatum and E. pauciflorum than E. macrophyllum. This phylogenomic evidence also suggests Erythroxylum sect. Macrocalyx, to which E. macrophyllum belongs, is a polyphyletic taxonomic section. We thus propose elevating this variety to specific status, as Erythroxylum savannarum. We provide an updated taxonomic description, information about its habitat and distribution, and justify its informal IUCN cat- egorization of Near Threatened (NT)
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Taxonomic and nomenclatural novelties in Marcetieae (Melastomataceae) from Colombia: A new species of Ernestia and the identity of Acisanthera goudotii
During the development of the taxonomic treatment of Ernestia we came across a taxonomic novelty and a species for which taxonomic verification was needed from Colombia. Herein, we propose Ernestia rheophytica a new species belonging to the sensu stricto clade of the genus, and clarify the identity of Acisanthera goudotii, now treated as E. goudotii. We also clarify the status of the original material of E. goudotii and propose the lectotypification of E. ovata and its synonymization under E. goudotii. Ernestia rheophytica, as the name indicates, is a rheophytic species, a rare habit in Melastomataceae, especially in Marcetieae.
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- PAR ID:
- 10626917
- Publisher / Repository:
- Magnolia Press
- Date Published:
- Journal Name:
- Phytotaxa
- Volume:
- 677
- Issue:
- 2
- ISSN:
- 1179-3155
- Page Range / eLocation ID:
- 109 to 124
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.11646/phytotaxa.677.2.1
