Nearly 21,000 species including conifers, freshwater shrimps, cone snails and the Yangtze Finless Porpoise are about to go extinct, according to the updated IUCN Red List.

The international Union for Conservation of Nature (IUCN) has now added 4,807 species in its latest "Red List", bringing the total number of threatened species to 70,294, of which 20,934 are on the edge of extinction.

Also, The Santa Cruz Pupfish, Cape Verde Giant Skink (lizard) and a species of freshwater shrimp have been declared extinct.

"Thanks to the IUCN Red List, we now have more information on the state of the world's biodiversity than ever before. But the overall picture is alarming. We must use this knowledge to its fullest - making our conservation efforts well targeted and efficient - if we are serious about stopping the extinction crisis that continues to threaten all life on Earth," said Jane Smart, Global Director, IUCN Biodiversity Conservation Group, according to a press release.

According to the update, over a third of all conifers are now facing extinction. Over 200 of the total 606 species of pine, fir, cedar and other conifers could soon be lost forever if strong measures aren't taken to conserve them. Conifers are the biggest and oldest living organisms on earth. Some conifer species such as Bristlecone Pine (Pinus longaeva) can live for over 5,000 years and Coast Redwood (Sequoia sempervirens) can grow to a height of 110 meters.

The loss of the conifer forests is also bad because they take-in more carbon dioxide than tropical or temperate forests.

The good news is that there are 33 species of conifers whose numbers have increased in the past few years and so have been moved to least-threatened category. For example, California's Monterey Pine (Pinus radiata) has been moved from threatened to least threatened in the latest update.

At least 28 species of shrimps along with 8 percent of cone snails are listed as threatened, IUCN said.

The update also showed that the Cape Verde Giant Skink- a type of lizard is extinct due to cats and rats that were introduced in its habitat; the Santa Cruz Pupfish (Cyprinodon arcuatus) is extinct due to lack of water and Freshwater Shrimp Macrobrachium leptodactylus is extinct due to loss of habitat.