MEXICO CITY (AP) — A species of snake that had been "lost" for almost 80 years has been re-discovered on a remote Mexican island. 
 
 According to a study published in the PLOS ONE scientific journal, the Clarion nightsnake was found again on one of the Revillagigedo Islands, more than 400 miles (650 kilometers) off Mexico's Pacific coast. 
 
 The original, and until recently the only, spotting of the species was made by American naturalist William Beebe in a 1936 visit to Clarion, one of the four Revillagigedo Islands. He returned with one snake preserved in a glass jar. 
 
 Subsequent visits failed to find more nightsnakes, and no further sightings were reported over the years from the island, which is inhabited only by a small detachment of Mexican marines. The existing dead sample was assumed to be a labelling error and the snake was largely struck from taxonomic registries. 
 
 But Daniel Mulcahy, a researcher for the National Museum of Natural History in Washington, suspected it might still exist. He and Juan Martinez Gomez of Mexico's Ecology Institute set out to find it. 
 
 Martinez Gomez, an expert on the Revillagigedo Islands, noted the islands change a lot from season to season, so they timed the expedition last May to replicate Beebe's steps as they looked for the snake, which blends in with the island's rock formations and is largely active at night. And they used Beebe's original field notes as a guide. 
 
 "Basically, following those directions, we essentially put ourselves in his place," Martinez Gomez said. 
 
 One of his graduate students, Juan Alberto Cervantes, was the first to spot one of the snakes for the first time since 1936. 
 
 The researchers performed DNA analysis to establish the long, dark spotted snake as its own species and see where it had come from. The tests showed it is most closely related to snakes from Mexico's Sonora-Sinaloa coast more than 500 miles (800 kilometers) away. Martinez Gomez said the snake's ancestors may have made the trip from the mainland on a tree trunk felled by a storm and washed out to sea. 
 
 The National Museum of Natural History said Mulcahy "uncovered the controversy surrounding the inclusion of this snake in the scientific record, and found that it appears to be the only species ever to be discarded due to a presumed locality error." 
 
 Patricia Escalante, a biologist who curates bird collections at Mexico's National Autonomous University and who was not involved in the snake project, said the re-discovery of the Clarion nightsnake was "very interesting" and significant because of the fragility of island ecosystems. 
 
 One inhabitant of the Revillagigedo Islands, the Socorro dove, went extinct in its natural habitat sometime in the 1970s. But live specimens had been taken off the islands in the 1920s, and their descendants were recently re-introduced to the islands. ||||| Image copyright Daniel Mulcahy Image caption The Clarion Nightsnake has a distinctive pattern of spots Photo: Daniel Mulcahy 
 
 A lost species of snake that eluded scientists for nearly 80 years has been rediscovered in Mexico, a US museum says. 
 
 The Clarion Nightsnake was found on the Pacific island of Clarion in Mexico by a researcher from the Smithsonian Institution in Washington DC. 
 
 The snake was first discovered in 1936 by naturalist William Beebe. 
 
 Although never declared extinct, it was struck from the record after scientists were unable to rediscover it. 
 
 The museum said that researcher Daniel Mulcahy, working with an expert from a Mexican institute, carried out an expedition to Clarion Island where their team identified 11 snakes matching Beebe's description. 
 
 DNA tests confirmed that the Clarion Nightsnake was indeed genetically distinct from others found in mainland Mexico. 
 
 The museum said the snake species is found exclusively on the island and could have remained unknown to science if not for the team's efforts. It is now recognised as a full species. 
 
 "The rediscovery of the Clarion Nightsnake is an incredible story of how scientists rely on historical data and museum collections to solve modern-day mysteries about biodiversity in the world we live in," Mr Mulcahy said in a museum statement. 
 
 "Proper identification is the first step toward conserving this snake, and we plan to continue monitoring this species to learn more about the role it plays in the delicate Clarion Island ecosystem."
– The Clarion nightsnake is hard to spot, so hard to spot that for decades, the only sighting of the species native to one of Mexico's Revillagigedo Islands—the original sighting—was assumed to be a mistake. A joint US-Mexico team, however, managed to rediscover the species found by American naturalist William Beebe in 1936 by using his original field notes to retrace his steps and search for the nocturnal snake, which blends in with the island's rock formations, the AP reports. The expedition found 11 of the snakes, and DNA tests confirmed that the Clarion Island snake is a unique species, reports the BBC. The snake is related to snakes found on part of the Mexican coast more than 500 miles away, and researchers believe its ancestors may have arrived on a tree trunk washed out to sea long ago. Beebe returned from a visit to the island, located 400-plus miles off Mexico's Pacific coast, nearly 80 years ago with a snake preserved in a jar, but his sample had long been considered a labeling error and his find was largely struck from taxonomic registries. The National Museum of Natural History praised the team's work, describing the snake as the "only species ever to be discarded due to a presumed locality error." The rediscovery "is an incredible story of how scientists rely on historical data and museum collections to solve modern-day mysteries about biodiversity in the world we live in," the museum said in a statement.