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Miconia tetrandra, a morphologically distinctive species restricted to the Caribbean region, is provided with an updated assessment of its phylogenetic position and taxonomy. A detailed description and nomenclatural treatment are provided, along with a consideration of phenology, distribution and habitat, and citation of specimens examined. The species is a member of the Caribbean clade, and it is unusual within Miconia in having flowers with only four stamens (alternating with the petals), with short, obovate, yellow anthers that each open by two large pores. Miconia tetrandra is morphologically quite divergent from, but is likely related to, a clade comprised by M. angustifolia, M. urbanii, and M. biflora, and these three species traditionally have been included within the genus Tetrazygia. In contrast, M. tetrandra usually has been placed within Miconia.
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Biogeography and diversification of the Caribbean clade of Miconia (Melastomataceae): a Cuban origin underlies one of the largest Antillean radiations
Abstract The Greater Antilles are renowned as a biodiversity hotspot and known to be geologically complex, which has led, in part, to the generation of organismal diversity in this area. One of the most species-rich montane groups within the Greater Antilles is the tribe Miconieae (Miconia s.l.) of the Melastomataceae, with ca. 325 species found there. The most diverse clade of Miconia in the Caribbean, the Caribbean clade, composes roughly half of that diversity, with an estimated 160 species, nearly all of which are endemic to the Greater Antilles. It is unclear how that diversity has been generated through time or where it originated, but we now have sufficiently well-sampled and robust datasets to test these patterns. Using a custom-built plastome dataset, we generated a robust phylogenetic hypothesis for 106 of the 160 Caribbean clade members and tested biogeographical patterns among the islands. Our results suggest that the Caribbean clade originated in the mid-Miocene, probably from a South American ancestor, and diversified substantially on the island of Cuba before repeatedly dispersing across other parts of the Greater Antilles, especially into nearby Hispaniola and then, to a lesser extent, into Jamaica, Puerto Rico and, finally, into the Lesser Antilles.
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- PAR ID:
- 10470152
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Biological Journal of the Linnean Society
- Volume:
- 140
- Issue:
- 3
- ISSN:
- 0024-4066
- Format(s):
- Medium: X Size: p. 376-396
- Size(s):
- p. 376-396
- Sponsoring Org:
- National Science Foundation
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