Abstract Detail

Systematics

Bedoya , Ana Maria [1], Olmstead, Richard [1].

Andean uplift, drainage basin formation, and the evolution of riverweeds (Podostemaceae).

Riverweeds (Podostemaceae) are distict among angiosperms for their habit, living attached to rocks in fast-flowing water ecosystems such as river rapids and waterfalls. This family has a pantropical distribution with center of diversity in the Neotropics. The genus Marathrum extends from central America to northern South America and includes 22 species. However, given the high degree of modification that these plants experience in order to live in lotic environments, the taxonomic treatment is problematic. In this study, we focus on populations of Marathrum distributed across drainage basins in northern South America. Sequence capture and ddRadseq data suggest that drainage formation and isolation resulting from Andean uplift and landscape change drove isolation of populations, causing a strong pattern of genetic structure that is consistent with geography. Our results are in line with the current taxonomic treatment of the group and we find evidence of hybridization between species within drainage basins. We propose that the first and second pulse of Adean uplift did not results in drainage basin isolation in northern South America. Our project gives an insight into the classification, reproductive biology of the group, landscape change scenarios in northern South America, and the role of Andean uplift in shaping the evolution of riverweeds.

1 - University of Washington, Biology, University of Washington, Seattle, wa, 98195, USA

Keywords:
Andean uplift
hydrophytes
Podostemaceae
drainage basins
Target Enrichment.

Presentation Type: Oral Paper
Session: SYS3, Systematics III: Cooley Award presentations
Location: Virtual/Virtual
Date: Wednesday, July 29th, 2020
Time: 12:30 PM
Number: SYS3011
Abstract ID:431
Candidate for Awards:George R. Cooley Award