HMS Firefly was the Spanish schooner Antelope, which the British Royal Navy captured in February 1808 and purchased.

On 19 February 1808 HMS Meleager captured Antelope, a Spanish schooner Letter of Marque.

Antelope was pierced for 14 guns but only carried five, an 18-pounder midships and four 6-pounders; the 6-pounders she threw overboard during the chase.

She had a crew of 62 men and was sailing from Cadiz to Vera Cruz with a cargo of dry goods, brandy and wine.

Captain John Broughton of Meleager described Antelope as "a very fine vessel, sails well".