The SACC Baseline List and AOU are still struggling with the various races of the superspecies A. prasinus and a proposal is needed. Both the Sibley-Monroe and the Clement's list have split this one and call it Blue-throated Toucanet (Aulacorhynchus caeruleogularis maxillaris). Aulacorhynchus prasinus. Also known as Blue-throated Toucanet (Aulacorhynchus caeruleogularis maxillaris) in some circles. This bird appears to be part of a 'superspecies'. Here is some info I found searching the internet: A superspecies is a grouping of very closely related and largely allopatric species. This generally means that they have common ancestry but have developed over time into true species due to their geographic isolation. Allopatric is a fancy word referring to species that are geographically separated. The opposite is sympatric referring to species that occur in the same geographic area. I found this which appears to be a work in progress trying to sort out this superspecies: Navarro et al. in their paper Species limits in Mesoamerican Aulacorhynchus toucanets, Wilson Bulletin 113, 4 (2001): 363–372, discuss a taxonomic rearrangement of the forms of Emerald Toucanet. They tentatively come forward with a split into seven species, listed below. The porposed species and their ranges are: Wagler's Emerald-Toucanet A. wagleri sw Mexico: Guerrero & sw Oaxaca Blue-throated Emerald-Toucanet A. caeruleogularis Costa Rica; w Panama "Nelson's" Emerald-Toucanet A. cognatus c,e Panama; w Colombia: Chocó Santa Marta Emerald-Toucanet A. lautus nw Colombia: Santa Marta Mts. "Northern Andean" Emerald-Toucanet A. albivitta w Venezuela; Colombia: Andean slopes; Ecuador: e Andean slope "Peruvian" Emerald-Toucanet A. atrogularis s Ecuador: e Andean slope; Peru: e Andean slope & e lowlands; n,c Bolivia; w Brazil: Acre The geographic range of the form prasinus is e,se Mexico to c Nicaragua. More information can be found here toucanets