A species best known across the Alpha Quadrant for Tarkalean tea, Julian Bashir's usual drink, and seen on screen only as victims of the Borg in 2153.
The Tarkaleans are a spacefaring species whose name is attached to one of the most frequently ordered drinks on Deep Space 9. Tarkalean tea is Bashir's regular choice at the replimat and at Quark's, and it is mentioned from Past Prologue through to What You Leave Behind.
The only Tarkaleans seen on screen appear in the Enterprise episode Regeneration. Enterprise answers a distress call from a Tarkalean freighter attacked by Borg who had been revived in the Arctic, and brings two survivors aboard. Both have been infected with nanoprobes. They turn on the crew, inject Phlox, and are finally blown out of an airlock by Archer.
T'Pol also refers in Dead Stop to a Tarkalean device able to replicate objects, and Starship Down mentions Tarkalean sheep herders.