Scientific note: southernmost record of Mourella caerulea and evidence of old and gradual colonization to the south

Little is known about the native bees of Uruguay and no scientific research has been carried out until now. This study aimed to contribute to the knowledge of the native bees, still greatly undermined in Uruguay. To achieve that, workers from the potential species were collected from different locations of the country. Firstly, they were morphologically identified through a taxonomic key and complemented with the Cytochrome Oxidase subunit I sequence, used to infer phylogenetic trees and a haplotype network together with others available in Genbank. Nest characteristics and both morphological and molecular analyses confirm the presence of Mourella caerulea in Uruguay, which constitutes the southernmost formal record of the species. Population analyses suggest that M. caerulea could have colonized the region from the north, slowly and gradually, through the upper regions of the Pampa’s plain.