Thomas Tew (active from 1691 to 1695 in Indian Ocean and Caribbean waters) is reputed to have been the first pirate to fly a black Jolly Roger --one depicting no skull or bones though, but an arm brandishing a cutlass, so showing close resemblance to the bloedvlag design often used by European navies and Barbary corsairs too.
It is unlikely such flag was used as a regular ensign, but rather as a signal flag, hoisted from a mast for identification purposes, or when action was close.
Sizes: ensign W12 x L18 mm, mast flags W8 x L12 mm, jack W6 x L9 mm, pennant W4 x L48 mm.