The latest update to the IUCN Red List of Threatened Species was published Monday and, as you can imagine, it wasn't good news. The Red List, the global inventory of species, now identifies 22,413 species as threatened with extinction around the world.

Some of the most notable of the 310 additions to the Red List are heavily overfished species. Worst off is the Chinese pufferfish (Takifugu chinensis), which the IUCN say has experienced a 99.99 percent population decline over the past 40 years and is now critically endangered. The Pacific Bluefin tuna (Thunnus orientalis) has been assessed as vulnerable to extinction, one step below endangered. It joins the Atlantic Bluefin (T. thynnus), which was assessed as endangered in 2011. Similarly the American eel (Anguilla rostrata), which fishermen have turned to after causing the near-extinction of Japanese and European eels, has been listed as endangered.

Not every overexploited species lives in the sea. The Chinese cobra (Naja atra), which the IUCN says is "among the top animal species exported from mainland China to Hong Kong for the food market," has been added to the list as vulnerable.

The update also, sadly, puts the final nails in the coffins of several species that have been unseen for decades and have now been classified as extinct. Two Turkish fish, the Gölçük toothcarp (Aphanius splendens) and the Eğirdir minnow (Pseudophoxinus handlirschi), were wiped out by non-native, introduced fish. A fish from Israel called the long jaw tristramella (Tristramella sacra) disappeared after its marsh habitat was destroyed. The St. Helena giant earwig (Labidura herculeana), which once lived on the island for which it is named, was probably wiped out by a variety of invasive species, including rats, mice and spiders. A Malaysian mollusk called Plectostoma sciaphilum disappeared after its only known habitat was mined for limestone. Finally, an invertebrate called Geonemertes rodericana probably disappeared nearly 100 years ago after its only home on the island of Rodrigues in the Indian Ocean was deforested.

These extinctions won't be the last. The Red List update also contains quite a few species that are now listed as "critically endangered (presumed extinct)." These are yet more species that have been unseen for decades, but scientists haven't given up looking for them yet.

The IUCN Red List has grown dramatically over the past two decades, not just because of the increasingly level of threats faced by species around the world but also because of efforts to assess all species around the world. Still, it is not comprehensive. Although all known mammals and birds have been assessed for their extinction risk, scientists have yet to determine the risks facing 56 percent of reptiles, 62 percent of fish, 94 percent of plants, 95.5 percent of insects and 99.997 percent of mushrooms. All told, the IUCN calculates that only four percent of the estimated 1.73 million species on the planet have been studied enough to understand their risks and the stability of their populations.

Previously in Extinction Countdown:

Photos courtesy of IUCN