Molecular analysis confirms Agama picticauda invasion on Western Indian Ocean islands

Abstract

The Western Indian Ocean biodiversity hotspot hosts a remarkable array of endemic species, but invasive alien species increasingly threaten its unique ecosystems. Lizards of the West African Agama agama species group are successful colonizers, with recent introductions to Grande Comore (Comoros Archipelago) and Reunion Island. Systematic revisions within the native range of the A. agama species group have left many of the introduced populations without clear identity. We used molecular methods to determine the identities of the Agama species introduced to Grande Comore and Reunion Island, define their respective likely origin, and assess body size characteristics for each island population. We identified Agama picticauda as the species present on both islands with likely origins in two distinct Western African regions. Agamas from Reunion Island had longer and wider heads with greater body weight than Grande Comore individuals. Sexual size dimorphism on both islands was driven by weight, with males being heavier than females. We provide foundations for further research on the ecology and impacts of A. picticauda on Western Indian Ocean islands and to aid in the development of targeted management strategies for controlling this invasive reptile.

Bibliographic Information