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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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Tuber luomae , a new spiny-spored truffle species from the Pacific Northwest, USA
Tuber luomae, a new truffle species known only from the Pacific Northwest, USA, is distinguished by spiny, nonreticulate spores and a two-layered peridium — the outermost layer (pellis) consists of inflated, globose to subpolygonal cells and the inner (subpellis) of narrow hyphae. ITS sequence analyses show that it has phylogenetic affinity to other Tuber species in the Rufum clade. The only other members of the Rufum clade with a strongly developed peridiopellis of large, inflated cells are the southern European T. malacodermum and T. pustulatum and the northern Mexican T. theleascum . We find it interesting that this peridial structure that is uncommon in the Rufum clade has been found in geographically disjunct species.
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- Award ID(s):
- 1946445
- PAR ID:
- 10205675
- Date Published:
- Journal Name:
- Fungal Systematics and Evolution
- Volume:
- 6
- Issue:
- 1
- ISSN:
- 2589-3823
- Page Range / eLocation ID:
- 299 to 304
- 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/10.3114/fuse.2020.06.15
