In a discovery that a Smithsonian Institution scientist calls a ''lollapalooza'' of a find, an amateur paleontologist has unearthed a prehistoric graveyard of 1.5 million-year-old animals.
Frank A. Garcia says he discovered the site in June 1983 in a pit that had once been a South Hillsborough County tomato field.
Only a small portion of the site has been excavated, and fossil experts say it has the potential to be one of the most significant paleontological finds for that time period in the nation. During the last six months, Mr. Garcia has been excavating an area he believed had once been the bed of a prehistoric river that had attracted a wide range of animals.
The fossilized skeletons of the animals that Garcia found show that Florida's original settlers were far different from the present inhabitants. Vying for use of the river, he says, were saber cats, a jaguar, timber wolves, giant armadillos, bears, mammoths, a colony of camels, small horses, and a condor with a 15-foot wing span.
The new site ''has to be right up there with the very best finds of this age anywhere,'' says Clayton Ray, Smithsonian curator of paleobiology. ''It has to be the richest in the United States.''
Many of the specimens Garcia has found have been checked by scientists at the Florida State Museum in Gainesville. S. David Webb, the museum's curator of paleobiology, says he has been to the site, and information of the finding has been forwarded to the Smithsonian Institution in Washington.
Dr. Webb says the find is ''extremely significant. It's so big, we don't understand all of the ramifications yet.''
The fossil record of this particular time in the development of life is scant , he explains, because the ice age wiped out large parts of the record in areas north of Florida.
''This is like finding a new chapter in the history of life,'' he says. ''It will fill in a lot on the chapter that is weak.''
He says that among the animals already disovered in the dig, tentatively identified are:
* ''A uniquely rich sample'' of a small llama that may be new to science. Much research will have to be done to determine if it is a dwarf species.
* A large bird that appears to be like a California condor. No specimen as complete as the one found in Hillsborough County has ever been discovered in the eastern half of the country.
* A small saber-toothed cat that fills in a gap in the record of the development of saber-toothed tigers.
* A small ground sloth that previously had been known to exist only in the arid Great Basin area in the west.
''This is a potentially extremely exciting find,'' says Webb, ''but it will take years of study to fully appreciatd what has been found.''
Professional scientists are full of praise for the work that Garcia has done as an amateur.
''There's no money in vertebrate paleontology,'' Dr. Ray says. ''He (Garcia) does it as a labor of love. He's an amateur in the best sense of the word. He's a full pro when it comes to field work, but he just doesn't make any money at it.''
Ray says a lot of significant paleontological sights probably have been destroyed inadvertently in Florida by phosphate mining and pit excavation. The state is so flat that fossils are not uncovered by erosion, he explains, so if anything is to be found, someone must have the energy and time to dig.
While animal life in Florida was once considered to have developed separately from the rest of North America, Ray says, Garcia's finds will help prove that animals throughout North America were related.
Garcia says he had been trying to pinpoint the course of the prehistoric river for the past three or four years, and he finally found it under four feet of overburden in the pit. After extracting a sample of fossil, he and his associates covered over the pit until they have more time for a thorough excavation.
Stories about Garcia's discoveries in central Florida during the past decade are plentiful. An asbestos worker by trade, Garcia spends much of his free time sifting through pits, phosphate mines, and riverbeds looking for evidence of life in Florida's remote past.
He has no formal training in paleontology, and he has never gone to college. But he says his interest in searching for ancient bones has been intense since he was eight years old and found his first bottle on his grandfather's Lake Okeechobee farm.
''I like discovery,'' he says. ''It's exciting. That's what life's all about. The incredible part is that Florida is the most spectacular peninsula in the world for fossils.''
Nearly 15 years ago he found the fossil of a previously undiscovered extinct variety of antelope that has since been named for him: Antilocapra (Subantilocapra) Garciae.
In 1981, the Smithsonian named him a research collaborator, and he has received a small Smithsonian grant to help him with his travel expenses while looking for prehistoric sea cows in the Tampa Bay area.
''I have a knack for going out and finding these things,'' he says, explaining how someone with no formal education can be so good at a technical subject. ''They (Smithsonian officials) told me they were not interested in degrees, but in results.''