Saint Lucia Racer (Liophis ornatus): This critically endangered snake is found only on the Caribbean island of Saint Lucia and is one of the rarest snakes in the world.
Antiguan Racer (Alsophis antiguae): Another critically endangered snake, the Antiguan Racer is endemic to the island of Antigua in the Caribbean. It was once on the brink of extinction but has shown signs of recovery due to conservation efforts.
Aruba Island Rattlesnake (Crotalus durissus unicolor): This snake is endemic to the island of Aruba in the Caribbean. It is listed as critically endangered and faces threats from habitat loss and introduced predators.
Round Island Keel-scaled Boa (Casarea dussumieri): Found only on Round Island and a few islets in the Indian Ocean, this snake is critically endangered. Its population is severely fragmented, and it is threatened by habitat degradation.
Cuban Boa (Chilabothrus angulifer): Endemic to Cuba, this species is critically endangered and has a restricted range. It faces threats from habitat loss and illegal collection for the pet trade.
Madagascar Ground Boa (Acrantophis madagascariensis): This large boa is endemic to Madagascar and is listed as vulnerable. It is threatened by habitat destruction and collection for the pet trade.
Santa Catalina Island Rattlesnake (Crotalus catalinensis): Found only on Santa Catalina Island off the coast of California, USA, this snake is critically endangered. Its population size is very small and vulnerable to habitat loss and introduced species.
Sipora Pit Viper (Parias hageni): This venomous snake is endemic to the Mentawai Islands in Indonesia. It is rare and known from only a few specimens.
Iranian Mountain Viper (Montivipera latifii): This viper is found in the Zagros Mountains of Iran and is considered rare. It has a restricted distribution and faces threats from habitat destruction.
Banded Rock Rattlesnake (Crotalus lepidus klauberi): Endemic to a small area in the state of San Luis Potosi, Mexico, this subspecies of the rock rattlesnake is considered rare and has a limited population.