Third pygmy marmoset found safe after being taken from Symbio Wildlife Park south of Sydney.

The third pygmy marmoset monkey stolen from a wildlife park south of Sydney has been found alive and well, New South Wales Police have confirmed.

The monkey, named Gomez, was found in Tahmoor on Monday night following reports the animal had been left in a box on a front doorstep.

Police said Gomez would be returned to Symbio Wildlife Park in Helensburgh, where he will be reunited with the two other monkeys who were also stolen on Saturday.

Zoo staff earlier said they believed there was a financial motivation behind the theft of the rare animals — Gomez, Sophia and a four-week-old that had yet to be named.

On Sunday, a call to Crime Stoppers led police to search a vehicle in Appin 30 kilometres from the park.

Police found the youngest marmoset alive in the car and arrested brothers Jackson and Jesse George.

Officers found the second marmoset, Sophia, in the Campbelltown area.

The brothers were charged with various offences and pleaded guilty when they appeared in Campbelltown Local Court on Monday.

Neither brother is alleged to have been involved in the direct theft of the monkeys, and Jackson George was only found in possession of one of them.

He pleaded guilty to dealing in the proceeds of crime and will reappear in January for sentencing.

Jesse George pleaded guilty to driving his brother, knowing there was a stolen monkey in the car at the time.

He was sentenced to a two-year good behaviour bond and given a $1,500 fine.

Police said investigations into the theft would continue and are urging anyone with information in relation to the incident to call Crime Stoppers.

This post originally appeared on ABC News.