The Ghorusdans were a species native to Ghorusda.
Ghorusdans had values that were very complex and differed greatly from Federation values; furthermore, they had a large number of cultural taboos.
When first contact was attempted with the species in the 24th century, the Federation sent a specialist, the Betazoid Tam Elbrun, to handle the difficult situation. Elbrun got too involved with the Ghorusdans, however, and first contact went fatally wrong, resulting in the deaths of 47 crewmembers of the USS Adelphi. This tragic incident was known as the Ghorusda Disaster from then on. (TNG: "Tin Man")