©Kiko Gómez & Xavier Espadaler
Notes on the genus
In the Iberian Messor species exists a continuus degree of polimorphism. A group of species (M. celiae, M. hispanicus, M. lobicornis) can be named as monomorphic, as the size of the workers is quite similar to the variation know in Messor. Another group (M. barbarus, M. bouvieri, M. capitatus, M. marocanus, M. structor, M. timidus) is clearly polimorphic. But, as usual happens in Nature when we're trying to dicotomyze reality, there's one species (M. lusitanicus) with a polmorphism in the middle of these two groups. The degree of polimorphism is a valid characteristic in species diferentiation for some pair of species.
In order to achieve a reliable identification it is advisable to use workers of all sizes.