Conservation charity Buglife is petitioning Highland Council to protect Fonseca’s seed fly and its home from development. The fly is restricted globally to a short stretch of coast nearby.
"The habitat within the proposed 236-hectare golf course is similar, so the inference is that the fly should be there too," said Buglife conservation director Craig Macadam.
Its population is thought to be closely associated with ragwort, sow-thistle and local sand dunes. The fly is named after the British dipterist Evelyn Cecil Muschamp d’Assis-Fonseca, 1899 to 1993.
"Stabilisation of the dunes and creation of fairways and greens for the proposed golf course will destroy the habitat for the species and further fragment the already fragile population."
Recent survey work by Scottish Natural Heritage (SNH) found populations had dropped significantly since the 1970s and 80s.
SNH was unable to survey the proposed golf course, however the fly is expected to be present there as it forms a suitable habitat.
Macadam concluded: "Scotland has an international responsibility for this species. Its habitat should be protected and enhanced, not put under threat from yet another golf course development."