West Dunbartonshire (UK): He is a third of the size of an average guinea pig, and weighs in at just a few ounces - but this tiny puppy could be a big deal when it comes to world records.
The miniscule chihuahua-Jack Russell cross - appropriately named Tom Thumb by its owners - is a serious contender for the title of being the smallest dog on the planet.
Little Tom was born just three weeks ago as part of a surprise litter to his mom, Spice, a chihuahua.
And he is unlikely to get much bigger - with some previous experience of rearing puppies through their early weeks, his owners are convinced that Tom is almost fully grown now.
