Mara Lamboy of the Dept of Animal Care and Control holds Cheyenne, who was found strolling down Divisadero Street

Cheyenne was just a distant memory when Edwards got a call from her county shelter three weeks ago. The cat had been found -- 3,000 miles away, in San Francisco.

"I figured, there's no way that's my Cheyenne," Edwards said. "I told them, 'I had a cat named Cheyenne, but I've never lived in San Francisco.' "

Someone found the black, short-haired cat strolling down Divisadero Street and dropped her at the Department of Animal Care and Control on April Fool's Day. When workers scanned her for a microchip and found she had been lost in Florida seven years earlier, they wondered if it was a gag.

"Maybe she came here on vacation because she wanted to see the Wine Country, and decided to stick around because it's not so muggy," joked Deb Campbell, spokeswoman for Animal Care and Control, as she cradled Cheyenne at her temporary home in the shelter.

The more probable, if prosaic, explanation is that a former neighbor of Edwards' found the cat, decided to keep her, then moved to San Francisco.

"She has glossy fur, good weight," Campbell said. "She definitely looks in good condition, so I don't think she walked here."

No one has contacted Animal Care and Control claiming to be Cheyenne's owner. And because the microchip identifies Edwards as the owner, she retains legal rights to the cat, Campbell said.

The animal shelter in Manatee County, Fla., where Edwards adopted Cheyenne, was among the first in that state to implant microchips in its animals, said shelter director Keith Pratt. Lost pets that had chips implanted there have been found as far away as Germany, he said.

Long-distance reunions are new to San Francisco Animal Care and Control, said Mara Lamboy, an assistant supervisor. Most animals don't come from farther than Sacramento.

"For a cat missing across the country to be found several years later, that's a first for me," said Lamboy, who has worked at the shelter 15 years. "That connection never in a million years would have been made without a microchip."

Animal Care and Control is trying to find a way to return Cheyenne, now almost 10 years old, to Edwards. Campbell said Edwards wouldn't be on the hook, but the agency can't afford to ship Cheyenne cross-country and has been searching for a traveler to carry her by plane.

Edwards hopes to get Cheyenne back. But she also has some concern about how the cat will feel about a reunion, given that the family has picked up three cats since Cheyenne left town.

"I feel sorry for Cheyenne because I'm sure she doesn't remember me," Edwards said. "I'm hoping that she'll merge nicely with our other cats."

E-mail Simone Sebastian at sisebastian@sfchronicle.com.