cross river gorillaThe 2009 edition of the IUCN Red List of Threatened Species was released today, and the news isn't good: 17,291 species out of 47,677 assessed species, or 36 percent, are threatened with extinction.

Science currently recognizes around 1.8 million species on Earth (out of an estimated five million to 30 million total species—the true total remains unknown). But the health of the vast majority of those known species has yet to be assessed. Even among those on the IUCN's list, 14 percent lack enough information to judge their health (or threat level) in the wild.

Below is a breakdown of the endangered species' status on the new IUCN list:

• Extinct: 809

• Extinct in the Wild: 66

• Critically Endangered: 3,325 (of these, 257 species are listed as "possibly extinct")

• Endangered: 4,891

• Vulnerable (to extinction): 9,075

• Near Threatened: 3,650

Definitions of the IUCN's categories can be found here.

Last year's list assessed 44,838 species; information on more than 2,800 additional species has been added in 2009. This includes more than 1,300 previously unassessed dragonflies and damselflies, of which the IUCN recently completed a major new study.

Amphibians seem to be facing the greatest threat, with 1,895 of 6,285 assessed species in danger of extinction. One amphibian species, the Kihansi spray toad (Nectophrynoides asperginis), has been moved from the IUCN's Critically Endangered list and is considered Extinct in the Wild. The deadly chytrid fungus is blamed for the species's final death note as well as for many other declines in amphibian populations over the past few years.

"These results are just the tip of the iceberg," said Craig Hilton-Taylor, manager of the IUCN Red List Unit, in a prepared statement. "There are many more millions [of species] out there which could be under serious threat."

Image: The Cross River gorilla (Gorilla gorilla diehli), one of the Critically Endangered species assessed by the IUCN Red List of Threatened Species. Via Wikipedia