A DNA study has determined that the giant tortoises that inhabit the island of São Cristóvão, in the Galapagos, correspond to a new species that has not yet been described by science, the Ministry of the Environment of Ecuador reported on Thursday (10).
“The species of giant tortoise that inhabits the island of São Cristóvão, until now scientifically known as Chelonoidis chathamensiscorresponds genetically to a different species,” the folder said on its Twitter account.
Researchers from the University of Newcastle, Yale University, the Galapagos Conservancy and other institutions compared the genetic material of the tortoises that currently inhabit the 557 km-long island with bones and shells collected in 1906 by the California Academy of Sciences in a cave in the highlands of the island.
When the description of Chelonoidis chathamensisthe expeditionary group that collected the bones from the cave never reached the lowlands of northeast São Cristóvão, where the turtles currently live.
With that, “scientists concluded that the nearly 8,000 turtles that exist today in São Cristóvão cannot be chelonoidis chathamensisbut rather correspond to a completely new lineage,” the Environment Ministry said in a statement.
The US NGO Galapagos Conservancy added in a bulletin that the island’s highland group “is almost certainly extinct” and that not one, but two different varieties of tortoise inhabit the site – one that lived in the highlands and the other in the lowlands.
Danny Rueda, director of the Galapagos National Park (PNG), commented that “this discovery for the Galapagos demonstrates the constant genetic variability” of species in the archipelago, located 1,000 km off the coast of Ecuador.
The study, which was published in the scientific journal Heredity, will continue with the recovery of more DNA from bones and shells to clarify whether live St. Kitts tortoises should be given a new name.
Millions of years ago, the island may have been divided by the sea and each part had its own species of turtle.
But once the water level dropped, the two islands merged, as did their turtles.
Galapagos, a Natural Heritage Site with unique flora and fauna in the world, was named after the giant tortoises. There were originally 15 species of giant tortoises on the archipelago, three of which went extinct centuries ago, according to the PNG.
In 2019, a specimen of Chelonoidis phantastica was found on Fernandina Island after more than a hundred years considered extinct.
