The Jamaican Mango (Anthracothorax mango) - also known as Black Hummingbird or Black Mango Hummingbird - is found only on the island of Jamaica.
The plumage is blackish with attractive iridescent magenta streaks on the cheeks down to the neck, bronze/orange sheen on the shoulders, and blue, green and bronze/orange streaks over most of the body.
Their black bills are down-curved.
Juvenile males interestingly have blue throats until they are about two years old.
Males establish feeding territories, where they aggressively chase away other males as well as large insects.

I was lucky to find this male stretching his tail and wings (1st photo) and showing his stunning colours in the garden of my B&B.

Tamarind Great House B&B garden, Saint Mary, Oracabessa, Jamaica, 20 January 2018