In a study published today in the open access journal BMC Evolutionary Biology, a team of researchers from Madagascar and Europe identified new species of lemurs based on differences in a specific gene sequence. The new species also live in distinct geographical areas. They had not been identified from morphological differences or chromosome profiles ?the methods usually used to define species. These findings have important implications, as a better knowledge of lemur species characteristics will provide the basis for better conservation programmes for these endangered animals.
An international team comprising researchers from Madagascar, Germany, France and Switzerland classified individual lemurs on the basis of either their chromosome profile, called a 'karyotype', or the sequence of the mitochondrial cytochrome b gene. The team analysed the karyotypes of 99 individuals from all currently recognised species of lemur and the cytochrome b gene was sequenced in 68 individuals.
From the karyotypic profiles, Andriaholinirina et al. could identify individuals belonging to the eight currently recognised species of lemurs. On the basis of genetic differences in cytochrome b gene, however, the researchers identified three distinct species within the former species Lepilemur ruficaudatus and two distinct species within the former L. dorsalis. The newly identified species live in different geographic areas, separated by rivers, but show no obvious morphological differences.