Snakes, butterflies, and a number of exotic fish are on the brink of extinction, according to the latest list of the world's most endangered species.

The 50th annual Red List, from the International Union for the Conservation of Nature, claims there are more than 22,000 animal species whose survival is to some extent threatened.

At the latest List's launch in Sydney, the organisation blamed mankind's growing appetite for resources" - from food to fuel - for damaging global biodiversity.

The IUCN Director General Julia Marton-Lefevre said: "Each update of the IUCN Red List makes us realise that our planet is constantly losing its incredible diversity of life, largely due to our destructive actions to satisfy our growing appetite for resources.

"But we have scientific evidence that protected areas can play a central role in reversing this trend. Experts warn that threatened species poorly represented in protected areas are declining twice as fast as those which are well represented.

"Our responsibility is to increase the number of protected areas and ensure that they are effectively managed so that they can contribute to saving our planet's biodiversity."

Critically endangered species Show all 10 1 /10 Critically endangered species Critically endangered species Yangtze Finless Porpoise There are as few as 1,000 of this highly intelligent dolphin from the Chinese river of Yangtze. Wikmedia Critically endangered species Cross River Gorilla There are around 200-300 left in the wild. Wikmedia Critically endangered species The Amur Leopard There are only around 30 left, exclusively in the Russian Far East. Wikmedia Critically endangered species Black Rhino Improving numbers, but with fewer than 5,000 left in central Africa, it is critically endangered. Wikmedia Critically endangered species Hawskbill Sea Turtle Mostly threatened by wildlife trade; their shells highly valued. Wikmedia Critically endangered species Javan Rhino The most threatened rhino species - there are as few as 35 in Ujung Kulon National Park in Java, Indonesia. Wikmedia Critically endangered species Leatherback Turtle Having lost many of its habitable beaches, and impacted by fishing operations, this seaturtle is considered by WWF to be 'critically endangered'. Wikmedia Critically endangered species South China Tiger It is believed to be 'functionally extinct', with none of the species left in the wild. Wikmedia Critically endangered species Sumatran Elephant There are between 2,400 - 2,800 of this elephant native to Borneo and Sumatra. Wikmedia Critically endangered species Sumatran Orangutan There are an est. 7,300 but the gradual deforestation of their Sumatran habitat may threaten further. Wikmedia

Here's a look at some of the species singled out in the IUCN's report:

Fish

Overfishing for food has devastated the populations of underwater creatures, from tuna to eels. The Pacific bluefin tuna (Thunus orientalist) has seen its numbers decline by up to a third in the last two decades, going from a species of 'least concern' to 'vulnerable'.

Demand for the Japanese delicacy sashimi has led to some of the meaty tuna being valued at around £64,000.

The Chinese pufferfish (Takifugu chinensis), one of the world's most toxic fish, and a fellow victim of sashimi demand, has been moved to 'critically endangered' - the final category before extinction.

And the American Eel (Anguilla rostrata) is rapidly losing numbers, largely down to the lucrative Japanese fish market's pursuit of an alternative to the endangered Japanese eel.

(Flickriver)

Slugs and snails

The fluorescent Kaputar Pink Slug (Triboniophorus) exists exclusively on the highest levels of Mount Kaputar in New South Wales, Australia. Already listed as 'endangered', it is feared that rising temperatures due to climate change will leave it nowhere to go.

The Malaysian snail (Plectostoma sciaphilum) has been declared extinct following the destruction of its hill habitat by a large limestone quarrying company. Several other species in the region are also at risk.

Frogs

On the upside, two types of Colombian frog (Andinobates dorisswansonae and Andinobates tolimensis) have seen their fortunes improve due to environmental protections introduced for the forest in the Andes where they reside.

Snakes

The Chinese cobra (Naja atra) has been declared 'vulnerable' following a population decline of between 30 to 50 per cent over the last 20 years.

Though international trade of the cobra is regulated, the IUCN is pressing for conservative initiatives to protect the species, a delicacy in south east Asia.

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