Researchers have discovered eight of the top 25 most desired species lost to science in the five years since the hunt began, so they've added eight more.

The new species come from 17 different nations and were picked from a list of almost 2,000 vanished species.

In collaboration with the International Union for the Conservation of Nature (IUCN) Species Survival Commission, Re:wild maintains a list of all lost species.

Here are some new species that are very wanted
(Photo : ROSLAN RAHMAN/AFP via Getty Images)

'Fat catfish'

The Fat Catfish or Rhizosomichthys total has only ever been discovered 9,800 feet up in the Andes highlands, in Lake Tota, where the natives nickname it "Pez Graso," which translates to "grease fish" a term that is both suitable and worrisome for a flammable creature. Yes, you read that correctly.

Before the Fat Catfish went extinct, locals would occasionally use its fat as fuel in their lamps.

The mystery of their disappearance, on the other hand, remains unsolved.

The Fat Catfish was described for the first time in 1942 by ichthyologist Cecil Miles, and the last known wild specimen was caught in 1957. Before it, only nine other people had been identified.

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Togo mouse

The Togo Mouse or Leimacomys buettner was found in a single place in 1890. Because this species hasn't been reported since the two individuals gathered at the time are the only information we have concerning its natural history.

The Togo Mouse, according to researchers, may be found in areas of Ghana as well as Togo.

The contents of the Togo Mouse's teeth and stomachs show that the Togo Mouse's diet comprises insects. Its small tail shows that it lives on the ground rather than in the forest canopy.

Dwarf Hutia

The Dwarf Hutia, (Mesocapromys nanus) is one of the first mammals to be identified solely from a fossil, resembles a guinea pig-like rodent that previously roamed Cuba and the adjacent Isle of Youth.

It was last caught by researchers in 1937, but some suspicious poops discovered in 1978 may have been enough to indicate that it is still alive.

If it still exists, the Dwarf Hutia would most likely be found in the incredibly isolated Zapata Swamp, and there are likely just a few of them surviving.

Unlike other rodents, which frequently produce numerous offspring in a litter, a Dwarf Hutia that was kept in captivity back in the day only had one youngster.

South Island Kōkako

The South Island Kokako was last observed in 2007, making it one of the most recent species extinctions on our list of the top 25 most sought lost species.

The final officially accepted sighting of the South Island Kako, also known as the Orange-wattled Crow, made news in 2007.

Before then, the recognized record was in 1967. Based on this observation, the New Zealand Department of Conservation reversed its decision to declare the species extinct in 2008.

This bird's IUCN Red List status is Critically Endangered as of today (Possibly Extinct).

The South Island Kokako is recognized for its sad, sorrowful but beautiful singing, featuring rich flute and organ notes in its cries.

If this species is rediscovered, environmentalists in New Zealand think they can bring it back from the verge of extinction in the same way they helped bring back its sister species, the North Island Kokako, and other native birds like the Kkp, Takah, Black Robin, and Chatham Taiko.

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