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Title: Phylogenetic inference in section Archerythroxylum informs taxonomy, biogeography, and the domestication of coca ( Erythroxylum species)
Premise of the Study

This investigation establishes the firstDNA‐sequence‐based phylogenetic hypothesis of species relationships in the coca family (Erythroxylaceae) and presents its implications for the intrageneric taxonomy and neotropical biogeography ofErythroxylum. We also identify the closest wild relatives and evolutionary relationships of the cultivated coca taxa.

Methods

We focused our phylogenomic inference on the largest taxonomic section in the genusErythroxylum(ArcherythroxylumO.E.Schulz) using concatenation and gene tree reconciliation methods from hybridization‐based target capture of 427 genes.

Key Results

We show that neotropicalErythroxylumare monophyletic within the paleotropical lineages, yetArcherythroxylumand all of the other taxonomic sections from which we sampled multiple species lack monophyly. We mapped phytogeographic states onto the tree and found some concordance between these regions and clades. The wild speciesE. gracilipesandE. cataractarumare most closely related to the cultivatedE. cocaandE. novogranatense, but relationships within this “coca” clade remain equivocal.

Conclusions

Our results point to the difficulty of morphology‐based intrageneric classification in this clade and highlight the importance of integrative taxonomy in future systematic revisions. We can confidently identifyE. gracilipesandE. cataractarumas the closest wild relatives of the coca taxa, but understanding the domestication history of this crop will require more thorough phylogeographic analysis.

 
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NSF-PAR ID:
10371060
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
American Journal of Botany
Volume:
106
Issue:
1
ISSN:
0002-9122
Page Range / eLocation ID:
p. 154-165
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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