15 of the world’s rarest snakes

Saint Lucia racer (Erythrolamprus ornatus)

• IUCN estimated population of mature individuals: Less than 50
• Native country: Saint Lucia

Widely considered the rarest snake in the world, the Saint Lucia racer’s fate has been hanging by a thread: It was thought to be extinct between 1936 and 1973, but it was rediscovered in Maria Major island, about 1 km (0.62 mile) off the coast of Saint Lucia, where it used to be a common species before its disappearance.

Discover how ordinary objects work, and expand your understanding of the familiar.

SIGN UP

" height="20" alt="HEW Logo">

Thank you for signing up!"

Back to homepage

By clicking "Sign Up", you consent to the Britannica Privacy Policy and Terms of Use.

The Saint Lucia racer (also known as the ornate ground snake) first came under threat because of the introduction of invasive species, deforestation, and urbanization. It completely disappeared from Saint Lucia, with its numbers diminishing since the late 19th century, when Asian mongooses were first introduced. Its survival on Maria Major is dependent on conservation efforts. The Saint Lucia racer is nonvenomous, like other racers, and continues to face risks from inbreeding, hurricanes, wildfires, and invasive species from the mainland Saint Lucia. According to current estimates, there are fewer than 50 mature individuals left.

Jamaican racer (Hypsirhynchus ater)

• IUCN estimated population of mature individuals: Less than 50 (if not extinct)
• Native country: Jamaica

The Jamaican racer, or black racer, is also estimated to have fewer than 50 mature individuals left. It was common across Jamaica until the invasive species of small Indian mongoose was introduced in the early 1870s. No sightings had been documented since the early 20th century, and fears of its extinction remained until 2010, when a video shared by villagers in central Jamaica rekindled hopes that the species may have survived.

Orlov’s viper (Vipera orlovi or Pelias orlovi)

• IUCN estimated population of mature individuals: Less than 250
• Native country: Russia

Found in the Caucasus Mountains near the Black Sea coast, in forests, shrub land, and grasslands at elevations between 200 meters and 950 meters (about 600–3,000 feet), the Orlov’s viper is one of the 13–18 rare shieldheaded vipers in the Caucasus region. It was named in honor of herpetologist Nikolai Orlov. Noted as “extremely rare” by IUCN, its numbers have been declining steadily, and the species is under threat from the pet trade and other human activity.

Santa Catalina Island rattlesnake (Crotalus catalinensis)

• IUCN estimated population of mature individuals: Extreme fluctuations in populations*
• Native country: Mexico

Found on rocky hillsides and desert areas of Santa Catalina Island in the Gulf of California, Mexico, and once a common species, its population has been declining because of killings and capture for illegal trade. Its severely limited diet also puts it at risk. Surprisingly for a rattlesnake, this species lacks a functioning rattle and spends most of its time in trees.

Explore Britannica Premium!

The trusted destination for professionals, college students, and lifelong learners.

SUBSCRIBE

*From data collected between 2003 and 2004, IUCN reported wide fluctuations in the number of individuals recorded—from 0.23 (one snake every four person-hours of active searching) in June to 2.11 (two snakes per person-hour) in August.

Wagner’s viper (Montivipera wagneri)

• IUCN estimated population of mature individuals: Unknown; noted as “rare”
• Native country: Turkey

Concentrated mostly in the Aras River valley and found at altitudes between 1,200 and 2,000 meters (about 3,900–6,500 feet), this species is currently described as a rare species by IUCN, even though it was abundant a few decades ago. Over a period of 18 years, its population declined by 80 percent, owing to its collection for a thriving pet trade. Researchers view the Karakurt Dam, whose commercial operation started in 2020, as a further threat to its habitat.

Anatolian meadow viper (Vipera anatolica)

• IUCN estimated population of mature individuals: Unknown; noted as “extremely rare”
• Native country: Turkey

Known from a single location—Kohu Dag in southwestern Anatolia, Turkey—it is noted as an extremely rare species by IUCN. While there is a possibility that it may be found more widely, it has not been spotted outside the Kohu Dag region during multiple surveys, suggesting that it is a range-restricted species. It faces risk from the pet trade, persecution by local farmers, and possibly even from collection for scientific studies.

Saint Vincent black snake (Chironius vincenti)

• IUCN estimated population of mature individuals: Unknown
• Native country: Saint Vincent and the Grenadines

Another rare species previously thought to be extinct and subsequently rediscovered, the Saint Vincent black snake is known from Cumberland Forest Reserve, a single location, and is thought to occur over 22 square km (about 8 square miles) or less. Its population is at risk from clearings for marijuana plantations, declining forest cover, road and housing development, and predators such as the small Asian mongoose.

Roatán coral snake (Micrurus ruatanus)

• IUCN estimated population of mature individuals: Unknown; noted as “rare”
• Native country: Honduras

Because of its limited geographic range (see also endemic species) of less than 100 square km (about 40 square miles) and the fact that it is known from just a single location (the western part of Roatán island), the Roatán coral snake has been listed by IUCN as critically endangered. This is the only coral snake that is known to be endemic to a single island; other coral snakes are endemic to island groups and continents. Severe degradation of habitat from urban and agricultural expansion, tourist activity, and persecution by humans are some of the key threats faced by the species.

Clarion racer (Masticophis anthonyi)

• IUCN estimated population of mature individuals: Unknown
• Native country: Mexico

The Clarion racer is known only from Clarion Island, an uninhabited island in the Revillagigedo archipelago in Mexico. It has been spotted near nesting colonies of seabirds, whose nestlings it preys on, in addition to sea turtle hatchlings and lizards. It is threatened by introduced alien species and overgrazing.

Yoro Mountain forest snake (Omoadiphas texiguatensis)

• IUCN estimated population of mature individuals: Unknown
• Native country: Honduras

The Yoro Mountain forest snake is known from a single specimen found in Texíguat Wildlife Refuge (Refugio de Vida Silvestre Texiguat), a protected cloud forest area in Honduras spanning the departments of Atlántida and Yoro. There’s very little information about this rare species, and it is expected to be limited to the refuge, occurring over an area of only about 75 square km (30 square miles). Usually found in layers of fallen leaves, this species is reported by IUCN as declining and under threat from agricultural activity, excessive logging, and overall habitat degradation.

Atlántida dwarf brown snake (Rhadinella tolpanorum)

• IUCN estimated population of mature individuals: Unknown
• Native country: Honduras

The Atlántida dwarf brown snake shares many characteristics with the Yoro Mountain forest snake: It is found only in the Texíguat Wildlife Refuge, occurs over about 75 square km (30 square miles), is usually found in leaf litter, and is critically endangered because of agricultural expansion and timber extraction. It occurs at elevations of 1,690–1,800 meters (about 5,500–5,900 feet) above sea level.

Merendón Mountains snail eater (Sibon merendonensis)

• IUCN estimated population of mature individuals: Unknown
• Native country: Guatemala

The Merendón Mountains snail eater is known from a single specimen collected in 2008 in a cloud forest in La Montaña de las Granadillas, Guatemala. This cloud forest is separated from neighboring cloud forests by arid land, and researchers were unable to record any other specimens, so the species is assumed to be endemic to the mountain where the holotype (the first described specimen of a species) was found. It is under threat from habitat destruction resulting from agricultural activity and logging.

Kikuzato’s stream snake (Opisthotropis kikuzatoi)

• IUCN estimated population of mature individuals: Unknown
• Native country: Japan

Restricted to an area of just about 10 square km (about 4 square miles) in Kumejima island in the Okinawa island group, Kikuzato’s stream snake has shown a decline of about 90 percent between 1983 and 1998 in one of the two sites of the island where it is found. It gets a part of its common name from the streams where it occurs, alongside evergreen forests. The species is susceptible to water pollution and predation by bullfrogs, which are an invasive species in Kumejima Island, but has been given protection under Japan’s Act on Conservation of Endangered Species of Wild Flora and Fauna, which prohibits the capture of the snake.

Hong Kong blind snake (Indotyphlops lazelli)

• IUCN estimated population of mature individuals: Unknown
• Native country: Hong Kong

This snake is known from only two specimens found in the main island of Hong Kong, in 1988 and 1992; further surveys have not yielded any more sightings. Its limited distribution area and habitat destruction of one of the sites of recovery have presented a continuous threat to the species.

Golden lancehead (Bothrops insularis)

• IUCN estimated population of mature individuals: More than 2,000
• Native country: Brazil

The golden lancehead is known from a single location—Queimada Grande island off the coast of southeastern Brazil. The island, where many other snake species are found, is also known as Snake Island. This viper is found mostly in forest areas of the island and faces illegal capture for pet trade, even though conservation efforts such as a monitoring program and ex situ (away from its natural environment) breeding have been initiated.