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PremiseLeaf morphology is dynamic, continuously deforming during leaf expansion and among leaves within a shoot. Here, we measured the leaf morphology of more than 200 grapevines (Vitisspp.) over four years and modeled changes in leaf shape along the shoot to determine whether a composite leaf shape comprising all the leaves from a single shoot can better capture the variation and predict species identity compared with individual leaves. MethodsUsing homologous universal landmarks found in grapevine leaves, we modeled various morphological features as polynomial functions of leaf nodes. The resulting functions were used to reconstruct modeled leaf shapes across the shoots, generating composite leaves that comprehensively capture the spectrum of leaf morphologies present. ResultsWe found that composite leaves are better predictors of species identity than individual leaves from the same plant. We were able to use composite leaves to predict the species identity of previously unassigned grapevines, which were verified with genotyping. DiscussionObservations of individual leaf shape fail to capture the true diversity between species. Composite leaf shape—an assemblage of modeled leaf snapshots across the shoot—is a better representation of the dynamic and essential shapes of leaves, in addition to serving as a better predictor of species identity than individual leaves.
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Triolena anisophylla (Melastomataceae), a new and threatened species endemic to Panama
Summary A new species ofTriolena,endemic to Colón Province, Panama, is described and illustrated. The specimens of this taxon were previously identified asTriolena lanceolata, but closer inspection has shown them to be morphologically and geographically distinct.Triolena anisophyllaK.Samra & Michelang. grows on rocks and tree trunks along rivers in Colón Province. This species is distinguishable by its strongly anisophyllous leaves and unique trichomes on the adaxial surface of the leaves. A complete description, distribution map, preliminary conservation assessment, taxonomic notes, and regional key are provided.
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- PAR ID:
- 10544911
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Kew Bulletin
- Volume:
- 79
- Issue:
- 4
- ISSN:
- 0075-5974
- Format(s):
- Medium: X Size: p. 889-896
- Size(s):
- p. 889-896
- Sponsoring Org:
- National Science Foundation
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