Rapid speciation in Pacific Island Beetles


2006 to 2013


Carabid beetles of the genus Mecyclothorax speciate very rapidly in the isolated mountain ranges of Tahiti, with time between speciation as short as 300,000 yr. This very rapid speciation is due to complete isolation of very small populations of these species. All individuals of each species lack flight wings, ensuring that they are tightly tied to small habitat patches.


The very small distributional ranges of these species define geographic units that are biologically unique, and therefore candidates for individual conservation efforts. In Pacific Islands, where all fresh water is derived from rainfall, a healthy forest habitat at elevation is essential for the sustainability of human habitation.


Taxonomic revision has been accomplished that involved new description of 43 species, and complete revision of 108 species inhabiting Moorea and Tahiti. This revision is now in the hands of French Polynesian scientists, who routinely conduct biological surveys for plants and insects. They also conduct ongoing surveys for invasive species, especially ants, and will produce data on insect distributions that can be evaluated with the new taxonomic tools.


Since publication in October 2013, very likely little has been changed. Nonetheless, having the ability to identify the biological products collected during surveys will enhance the understanding of biodiversity in current time.

Submitted by: 

  • Liebherr, James K

Researchers involved: 

  • Liebherr, James K

Organizations involved: 

  • University of California-Berkeley

International focus: 

  • French Polynesia
  • United States of America

United States focus: 

  • Hawaii