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The Orchidaceae have about 28,000 currently accepted species, distributed in about 763 genera.
The determination of which family is larger is still under debate, because verified data on the members of such enormous families are continually in flux.
We then perform a new family-level analysis by integrating all 3 available fossils and using BEAST.
To evaluate how the newly estimated ages may influence the evolutionary interpretation of a species-level phylogeny, we assess divergence times for the South American genus Our results provide additional support that all extant orchids shared a most recent common ancestor in the Late Cretaceous (~77 million years ago, Ma).
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To restore access and understand how to better interact with our site to avoid this in the future, please have your system administrator contact [email protected] applying cladistic methods to a morphological character matrix, we resolve the phylogenetic position of M.caribea within the extant subtribe Goodyerinae (subfamily Orchidoideae). caribea to calibrate a molecular phylogenetic tree of the Orchidaceae.The diversification of appears even more correlated to late Tertiary climatic fluctuations than previously suggested.With the incorporation of new fossils in the orchid phylogeny and the use of a method that is arguably more adequate given the present data, our results represent the most up-to-date estimate of divergence times in orchids. A correct time estimation is essential for our understanding of the mechanisms underlying the diversification of orchids, and could contribute to discern between alternative hypotheses of diversification - such as significant increases in speciation rates temporally correlated to climatic changes, tectonic events, or radiation of pollinators.For example, the bee orchids (genus has an extremely long spur with nectar at the end, which led Charles Darwin to posit that this species was pollinated by a moth with a proboscis of unprecedented length.