A new species of blind cavefish has been discovered in the US - and it's already endangered.
This small 5-7.5cm/2-3in fish has been dubbed the Hoosier cavefish, with the scientific name of Amblyopsis hoosieri. It's the first North American cavefish to have been discovered in 40 years.
The new fish is found only in the caves of southern Indiana. Its natural habitat makes it extremely vulnerable to groundwater pollution.
Amblyopsis hoosieri is closely related to another endangered species, A. spelaea. In both fish the anus is located behind the head, rather than at the back of the body. The reason for this strange location is unclear, but as females brood their young in their branchial cavities, it may help the fish get fertilised eggs tucked into the gill chamber.
The article is published in the open-access journal ZooKeys.
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