Very local in tropical foothills of west Mexico; endemic. Favors oak woodland and shade-coffee plantations. Mainly feeds at low levels, often in shady gullies. Best detected by its distinctive, slightly liquid twittering calls. Male often looks blackish overall: note the black bill, dark blue tail, emerald gorget, and deep blue crown that sometimes catch the light. Female notably plain and drab: note plain gray face and underparts and black bill.