Many animals (and sometimes plants), such as Green Anoles in Michigan, are found only in a single greenhouse.
Convict Cichlids, swordtails, and guppies are established in a hotspring inside Grand Teton National Park.
Mexican Gray Squirrels are established on the small Elliot Key off southern Florida.
Black-and-green Poison Dart Frogs are found in a small patch of rainforest on Oahu (and also Maui apparently).
Greater Rheas are found in a small area of Germany.
Brush-tailed Rock Wallabies are found on a small area of mountain slope on Oahu.
Red-necked Wallabies are found on a small island off of Ireland.
The UW-Madison Arboretum in Madison, WI is home to several introduced plant species found nowhere else in the state.
African Clawed Frogs are established in Arizona only on a single golf course on the north side of Tucson.
Ensatina are established in a small area in northern Arziona.
Sockeye Salmon are introduced in Wisconsin only on one small isolated lake in the northeast part of the state.
There’s a species of scorpion (forget which one) established on a few acres in England.
Common Hippos are established in a small area of Colombia.
Eastern Chipmunks are established in ard around the grounds of the Wuppertal Zoo in Germany, where they escaped from several years ago.
Green Iguanas are found in the Jurong area of Singapore, also originating from zoo escapees.
Common Wall Lizards are established in Cincinnati, Ohio, they were released in the 70s.
Green Monkeys are found in and around the Miami airport.
Patas Monkeys are established on a small island off the coast of Puerto Rico.
This is one of my favorite subjects.