Shocked officers discovered crocodiles, monkeys and snakes during a raid on the static caravan on a farm on the outskirts of Perth.
Police and officers from the Scottish Society for the Prevention of Cruelty to Animals (SSPCA) discovered a mini zoo of live animals in the caravan.
Plumber Keith Colthart, 24, yesterday admitted trying to sell two protected animals by placing an advert for them on a website.
The ring-tailed lemurs were found in the caravan, along with three African dwarf crocodiles, monkeys, a spectacled cayman and nine snakes, including pythons and boa constrictors.
Colthart, from Wishaw, now faces being fined up to 10,000 or being sent to prison for a maximum of three months at Perth Sheriff Court.
He admitted a charge of trying to sell two ring-tailed lemurs through the Ad Trader website on 30 December last year from his then home at Gloagburn Farm, Tibbermore, by Perth.
He admitted offering to sell a protected species specimen contrary to the Control of Trade and Endangered Species (Enforcement) Regulations 1997.
Depute fiscal Stuart Richardson told the court: "Towards the end of December last year, word reached the SSPCA that the accused had placed an advert on the internet, advertising for sale two ring-tailed lemurs.
"To possess or try to sell animals such as this requires a special licence which is issued by a government department. He was not the holder of such a licence.
"Mr Colthart was living in a static caravan in a rural part of Perthshire at the time. Once (officers] gained admission to the caravan, they discovered in it a host of animals including dwarf crocodiles, a cayman and monkeys.
"All of the other animals were covered by a Dangerous Wild Animals licence. He had one of those.
"Unfortunately, also in the caravan were the two ring-tailed lemurs he did not have a licence for."
Sheriff Robert McCreadie said: "It is difficult to evaluate the seriousness of the issue unless I know a little bit more, like how highly endangered the lemurs are.
"I feel I would need to know a bit more about that before I could reach a view on sentence. The maximum sentence is a fine of 10,000."
Colthart was not present in court yesterday and the sheriff deferred sentence for him to appear personally and for the Crown to provide further information on lemur numbers.
The court was not told how much the lemurs were advertised for but it is thought they could be worth 4,000 each.