Compendium of American Amphitropical Vascular Plant Disjunctions

A compendium of examples of American amphitropical disjunctions (AAD), focusing (for now) only on vascular plants, with supporting data on chromosome number, dispersal direction, distribution, divergence time, propagule morphology, speciation rate, and taxonomy. Available here as an Excel spreadsheet.

Current number of AAD vascular plant examples: 237

These data stem originally from: Simpson, M. G., L. A. Johnson, T. Villaverde, and C. M. Guilliams. 2017. American Amphitropical Disjuncts: Perspectives from vascular plant analyses and prospects for future research. American Journal of Botany 104: 1600-1650.

Actively updated web pages, derived from the spreadsheets, are accessible at:

Bibliography of references pertinent to the study of AADs is available at:

Links pertinent to the study of AADs are tabulated here:

To join the American amphitropical disjunction Working Group ( 1) set up a (free) account in figshare; 2) email Michael Simpson ( your request. It should be processed within a day.

You may use the comments below to ask questions, make suggestions, or elicit conversations or collaborations concerning AADs.

To make a contribution toward updating this list of AAD vascular plants, you may:

1) Make a comment below regarding a needed change; and/or

2) Contact Michael Simpson ( with specific suggestions, including highlighting changes on the spreadsheet here.