Customs authorities have seized a parcel full of live venomous exotic snakes and spiders that smugglers attempted to get through by international mail.

Australian Border Force in Melbourne made the discovery after x-raying boxes marked "2 pair shoes".

What was in shoe box three ball pythons, or royal pythons

three ball pythons, or royal pythons two hognose snakes

two hognose snakes six vipers, identified as Wagler's temple vipers — a venomous pitviper species native to South-East Asia

six vipers, identified as Wagler's temple vipers — a venomous pitviper species native to South-East Asia two Colombian giant tarantulas

two Colombian giant tarantulas five Mexican redknee tarantulas

five Mexican redknee tarantulas two Brazilian salmon pink tarantulas - considered to be the third-largest tarantula in the world

two Brazilian salmon pink tarantulas - considered to be the third-largest tarantula in the world four Asian forest scorpions

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The parcel included six venomous vipers, native to South East Asia, nine large tarantulas from Mexico, Brazil and Colombia, plus Asian forest scorpions.

The Deputy Secretary for biosecurity Lyn O'Connell said it posed a risk of carrying pests and diseases that could affect human, animals and plants as well as agricultural industries.

The case is being investigated.

The detection is a win for Australia's Department of Agriculture and Water Resources, who is defending the recent increase in biosecurity failures, like red fire ants and white spot disease in Queensland prawns.

Explaining the complexity of the job, a biosecurity official said Australia received 1.7 million consignments of sea cargo and 18,000 vessels every year.

"It just goes to show you no two days are the same for Australian Border Force officers," Commander James Watson said.