Genus · Pseudoxyrhophiidae
Types of keeled snakes
2 species make up the genus Alluaudina, the snakes commonly called keeled snakes. None are considered dangerous to humans.
About Madagascar keeled snakes
A tiny genus of small, secretive keeled snakes found only on Madagascar.
Alluaudina is a genus of small snakes endemic to Madagascar, placed in the family Pseudoxyrhophiidae. That family is a large radiation of mostly harmless to mildly rear-fanged snakes centered on Madagascar and the nearby islands, and it includes the bulk of the island's snake diversity. Alluaudina holds just two recognized species, the Yellow-flanked Keeled Snake and the Ankarana Keeled Snake, which makes it one of the smaller branches within that group. The common name points to the keeled body scales that give these snakes a slightly rough texture rather than the smooth, glossy look of many relatives.
These are modest, slender snakes rather than large or showy ones. In general terms you recognize members of the genus by their small size, keeled dorsal scales, and the muted earth-toned patterning typical of leaf litter and forest floor dwellers, often with paler flanks suggested by the yellow-flanked species name. They live in Madagascar's forested habitats, including limestone karst regions such as the Ankarana massif that gives the second species its name. Because the genus is obscure and species records are limited, fine details of color and scale counts are best confirmed against a regional field guide rather than assumed from the genus alone.
On safety, Alluaudina belongs to a family where many members are rear-fanged with weak venom adapted to small prey, and none of Madagascar's snakes are considered a serious medical threat to people. These small snakes are not dangerous in the way a viper or cobra is, and there is no front-fanged venom delivery here. Even so, no wild snake should be picked up or handled, both for the animal's welfare and because any bite can cause local irritation or infection. If a person is bitten and develops unexpected or worsening symptoms, treat it as a medical matter and seek emergency care, in the United States via Poison Control at 1-800-222-1222 or local emergency services elsewhere. As forest-floor predators these snakes feed on small animals such as frogs, lizards, and invertebrates, and like most Madagascan pseudoxyrhophiids they are egg-laying.
Alluaudina belongs to the Pseudoxyrhophiidae family (Malagasy snakes). A spectacular radiation of mostly harmless snakes centered on Madagascar. Highly variable; identification is usually by region and genus rather than a single family trait.
Danger: Considered harmless to humans. Some are mildly venomous (rear-fanged) but not medically significant.
All species (2)
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