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Updated: Mar 1, 2026
10:23
A Concoction Pipeline for Generating Molecular Operational Taxonomic Units (MOTUs) Among Riparian and Aquatic Beetles
Published on: July 11, 2025
722
ORIGIN AND BIOGEOGRAPHY OF AESCULUS L. (HIPPOCASTANACEAE): A MOLECULAR PHYLOGENETIC PERSPECTIVE
Qiu-Yun Xiang1, Daniel J Crawford2, Andrea D Wolfe2
1Department of Biological Sciences, Idaho State University, Pocatello, Idaho, 83209-8007.
Summary
Phylogenetic analysis of Aesculus using molecular data reveals relationships mirroring geographic distribution. This study infers the genus originated in East Asia during the Cretaceous-Tertiary boundary, later spreading to North America and Europe.
Area of Science:
- Botany
- Molecular Phylogenetics
- Biogeography
Background:
- The Aesculus genus exhibits a disjunct distribution across Eurasia and North America.
- Previous classifications relied on morphological data, necessitating molecular validation.
Purpose of the Study:
- To reconstruct the phylogenetic relationships within the Aesculus genus using molecular markers.
- To infer the origin and biogeographic history of Aesculus.
Main Methods:
- Phylogenetic analyses using chloroplast gene matK and nuclear ribosomal RNA internal transcribed spacers.
- Ancestral character-state reconstruction.
- Molecular clock dating and integration of fossil evidence.
Main Results:
- Molecular data strongly correlate with existing geographic distributions of Aesculus species.
- Inferred phylogenetic lineages align with five previously recognized morphological sections.
- Evidence suggests Aesculus originated in high-latitude East Asia around 65 million years ago.
Conclusions:
- The genus Aesculus likely originated in East Asia and dispersed via the "boreotropical flora" during the Paleogene.
- Geological and climatic shifts in the Tertiary explain the current disjunct distribution of Aesculus.
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