Put your dog collars out for Wild Thang — the pooch that just came runner-up in the 31st annual World's Ugliest Dog Contest.

Key points: Scamp the Tramp, last year's runner-up, came out victorious

Scamp the Tramp, last year's runner-up, came out victorious Most competitors were previously abandoned or rescued from shelters across the US

Most competitors were previously abandoned or rescued from shelters across the US Organisers say the event is to promote adoption of dogs

The beady-eyed, disturbing-tongued Pekinese doesn't even get to call itself the world's ugliest after the ceremony in Northern California, in the US.

No ribbon, no cash prize, no official handshake and tummy rub for the three-year-old, which also featured in last year's competition.

And certainly no special appearance on television.

Tomorrow Wild Thang will still be an ugly dog, but not the ugly dog.

The grand prize went to Scamp the Tramp, who was last year's runner-up.

Scamp the Tramp's marvellous dreadlocks stole the show. ( AP: Noah Berger )

So for Wild Thang, there's always next year.

Scamp beat out 18 other contestants who showed off their droopy tongues, bowed legs, perpetually confused looks and other strange attributes.

The World's Ugliest Dog Contest has been running for 31 years. ( AP: Jeff Chiu )

The contestants got to walk the red carpet and preen for adoring fans at Sonoma-Marin Fairgrounds in the heart of Northern California wine country.

The competition, as they say, was fierce.

Owner Yvonne Morones of Santa Rosa, California, won an appearance with Scamp on the Today show, $US1,500 ($2,164) in cash, another $1,500 to donate to an animal shelter — and a trophy the size of a Rottweiler.

"He's Scamp the Champ, no longer Scamp the Tramp," Ms Morones told the Santa Rosa Press-Democrat after the victory.

"I think the audience saw his beautiful spirit and everything he's given back to the community."

Scamp makes volunteer visits to schoolchildren and a local senior citizens centre.

Scamp the Tramp is a fan of Bob Marley. ( AP: Noah Berger )

His matted black and grey hair, short legs and "extremely round body" were the physical attributes that saw him crowned champion, Ms Morones told the New York Times.

The street dog from Compton was rescued by Ms Morones in 2014 after she spotted him on Pet Finder.

"It was on the way home that I knew I made the right choice," she said in a contest press statement.

This dog named Puka didn't even make the top three. ( AP: Noah Berger )

"There we were, two strangers in a car on the way home to a new start. Bob Marley was playing 'One Love' and I looked over and little Scamp was bobbing his head."

"It was like he knew he had found his forever home."

Third place went to Tostito, a Chihuahua whose damaged ears and droopy tongue make him look like he just stuck his foot into an electrical socket. Tostito, owned by Molly Horgan of Falmouth, Maine, also won the Spirit Award.

This year's People's Choice Award went to Meatloaf, a bulldog mix with protruding teeth owned by Denae Pruner of Sacramento, California.

Everyone knows ugliness is in the eye of the beholder and, to a dog lover, there is no such thing as an uncomely canine.

Nineteen contestants went nose-to-nose in the annual competition. ( AP: Jeff Chiu )

Weird-looking, maybe. Appearance-challenged, perhaps. Or, as owners of ugly dogs like to say, "unique."

Like Willie Wonka, a sweet-natured pit bull abandoned after he was discovered to have a genetic malady that left his legs so bowed he could barely walk.

With a chuckle, publicist Christy Gentry said the competition wasn't just about being ugly.

"Judges are looking for special attributes like hanging tongues, slobber, drool (the more the better)," she explained.

"Maybe unusual patches of skin or hair."

Last year's champion, an English bulldog named Zsa Zsa, with a tongue that hung nearly to the ground, endeared herself to the judges when she sneezed and drooled all over them.

Soon she was headed to New York for national TV appearances.

Zsa Zsa got the glory in 2018. ( AP: Jeff Chiu )

Sadly, Zsa Zsa died about a year ago at age 9.

Another previous winner, Nana, made the cover of an album by the Grateful Dead spinoff band Ratdog.

Organisers say the contest isn't just skin-deep.

It's also about bringing attention to the needs of rescue dogs.

Scamp the Tramp is now Scamp the Champ. ( AP: Noah Berger )

Most competitors were previously abandoned or rescued from kill shelters in the US, found abandoned on streets or seized from unscrupulous breeders.

"What we're really doing is we're showcasing dogs that have been rescued and adopted and brought into loving homes," Ms Gentry said.

"These are sort of spokesdogs for adoption."

AP/ABC