However the act only classifies dogs as service animals - and makes no mention of snakes

Restaurant bosses said they could not ask the man to leave because it would have violated the Americans with Disabilities Act

He told shocked diners that it was his service animal and it helped him cope with his depression

A man who walked into a restaurant with a boa constructor was allowed to stay after telling workers there that it was a 'service animal'.

The unnamed male diner insisted he had to keep the snake with him at El Puente Mexican Restaurant in Nixa, Missouri, because it helped him with his depression.

When terrified customers asked the manager to throw out the man - and his pet - they were wrongly told the pair had to stay under disability laws.

The boa constrictor can be seen around the neck of the man in this Facebook photo taken by a fellow diner

The man said: 'It's my service animal and I'm allowed to have it because it helps me with my depression'

The manager of the restaurant in Nixa, Missouri, told scared customers that the snake would have to stay

The man entered the restaurant with a woman, who had the snake wrapped around her neck. She then passed it to the man, who wrapped it around his neck while they ate.

Fellow diner Lisa Loeffelholz, who was at the restaurant with her family, told KY3 News: 'The lady had the snake around her neck first and it started to slither off of her neck, down into the booth behind her.

'And she was pulling it, and I just started trembling and my mother said 'We've got to get out of here.'

Lisa Loeffelholz, who took the photo of the snake

After the woman passed the snake across the table to her male companion, Loeffelholz complained to the manager and took a photo.

She said the snake's owner told her: 'It's my service animal and I'm allowed to have it because it helps me with my depression.

'It's no different than having a dog service animal sitting here.'

Her mother, Terri Pitts, was so scared by the snake that she started trembling. The family asked their server if the restaurant could ask the man to take his snake elsewhere.

Loeffelholz said: 'The manager came over to us and said it was his service animal, so we have to allow him to stay.

'So that's when my mom and I and the girls decided that we would not stay.'

The restaurant boss could, in fact, have told the man to leave because dogs are the only 'service animals' mentioned in the Americans with Disabilities Act.

According to the ADA: 'The rule defines 'service animal' as a dog that has been individually trained to do work or perform tasks for the benefit of an individual with a disability.

'The rule states that other animals, whether wild or domestic, do not qualify as service animals.'

And Jill Finney, communications director for the city of Nixa, said the local police or animal control officers would have removed the reptile because it could have been a public safety concern.

Finney said of the restaurant bosses: 'Management didn't know what to do because they didn't want to violate anybody's rights, and that's understandable, but the patron could have then called 911.