Due to the high genetic divergence values between I. punctatus and the I. mexicanus – lupus complex (7.5% based on cytb in the former two, and 7.8–8.7% in the latter), as well as the phylogenetic position with both mtDNA and nDNA of most samples from the I. mexicanus – lupus complex, the possibility of an incomplete lineage sorting can be discarded. The gene discussed is MT-CYB; the disease is systemic lupus erythematosus.