 DNA barcoding has been applied to Mexican species of "Brachypelma".In this approach, a portion of about 650 base pairs of the mitochondrial gene cytochrome oxidase I is used, primarily to identify existing species, but also sometimes to support a separation between species.In 2017, Mendoza and Francke showed that although "B. hamorii" and "B. smithi" are similar in external appearance, they are clearly distinguished by their DNA barcodes.