FIGURE 3. Dorsal views of head of the non-melanic Micrurus spixii spixii (A—ZSM 203-1925) from municipality of Manacapurú, state of Amazonas, Brazil; melanic M. s. martiusi (B—FMNH 25222) from municipality of Barra do Tapirapé, state of Mato Grosso, Brazil; non-melanic M. s. obscurus (C—ANSP 21646) from municipality of São Gabriel da Cachoeira, state of Amazonas, Brazil; and melanic M. s. princeps (D—ZSM SN1) from province of Cochabamba, department of Cochabamba, Bolivia. Scale bar= 5 mm.