The Delhi Sands Flower-Loving Fly, which spends nearly all of its short life buried under a few sand dunes in Southern California's San Bernardino County, may emerge this week as the snail darter of the 1990s.

The once obscure and now federally protected fly is at the center of a major legal battle over the reach of federal environmental laws.A broad coalition of developers, farmers and property rights activists has urged the Supreme Court to take up a San Bernardino case and use it as a vehicle to restrict drastically the scope of the Endangered Species Act. San Bernardino officials are hoping to be freed from federal regulations that restrict development.

Since 1993, when the fate of the fly gained the attention of the U.S. Fish and Wildlife Service, it has cost the county and its taxpayers at least $6 million, officials said.

A new county emergency medical center had to be relocated slightly to avoid the sandy habitat of the inch-long insect, and a road leading to the facility had to be diverted. Because the flies will not flutter over asphalt or concrete, federal officials insisted on an unbroken sand corridor that would allow one group of flies to make contact with their neighbors a quarter-mile away.

At one point, a federal official suggested that traffic on a portion of the San Bernardino Freeway, which runs from the coast to the Arizona border, be halted or slowed in late August when the flies were out and about seeking mates.

"I think the system is out of control and something needs to be done," said Jerry Eaves, chairman of the San Bernardino County Board of Supervisors. "The Endangered Species Act was intended to save eagles and bears. Personally, I don't think we should be spending this money to save cockroaches, snails and flies."