An adult male of the pink iguana from the Galápagos on the rim of the crater of Volcan Wolf. The newly recognized species of iguana may already be endangered and could become extinct, scientists warn.
Photo courtesy of Gabriele Gentile
Had Charles Darwin explored the Volcan Wolf volcano when he visited the Galápagos in 1835 he might have spotted this pink land iguana, a species that originated in the islands more than five million years ago.
The northernmost volcano on the island of Isabela is the only home of the “rosada” iguana, a newly identified species of the land iguana Conolophus, scientists said today.
NASA image of Volcan Wolf created by Jesse Allen, using Landsat data provided by the United States Geological Survey
“Rosada” is the word for pink in Spanish. The two other known land species of iguana in the Galápagos, one of them also living on Isabel, are yellow.
Although Darwin noticed and commented on both marine and land iguanas of the Galápagos, he did not encounter a distinct form of land iguana that occurs only on Volcan Wolf, Gabriele Gentile of the Universitá Tor Vergata, Rome, Italy, and colleagues, reported in the journal Proceedings of the National Academies of Science.
“Perhaps even more surprising, this [rosada species of iguana]…remained unrecorded despite many other scientists having visited Volcan Wolf over the past century,” they wrote.
Adult male iguanas of the yellow (A and D) and rosada (B and C)) species
Photographs by Gabriele Gentile, as published in PNAS paper (see footnote below)
Genetic analysis of the rosada and other species of land iguanas performed by the scientists show that the rosada iguana diverged from the Galápagos’s other iguana populations more than five million years ago, when the archipelago was still forming.
Earlier genetic studies suggest that the split of the marine and land iguana lineages could have occurred as late as 10.5 million years ago, when the archipelago did not have the current configuration and none of the present islands had yet emerged, the paper noted.
“The ancient divergence between the rosada and other land iguanas — prior to the formation of the Volcan Wolf volcano — provides evidence for one of the most ancient diversification events recorded in the Galápagos,” the researchers said.
“Despite the attention given to them, the Galápagos have not yet finished offering evolutionary novelties,” the researchers wrote in their paper.
They called for efforts to conserve the new species before it becomes extinct.
Read the National Geographic News story about this discovery.
Authors of the paper “An overlooked, pink, new species of land iguana in the Galápagos,” in the journal Proceedings of the National Academy of Sciences, were: Gabriele Gentile, Anna Fabiani, and Valerio Sbordonia of Dipartimento di Biologia, Universitá Tor Vergata, Rome, Italy; Cruz Marquez of the Charles Darwin Foundation, Puerto Ayora, Galápagos Islands, Ecuador; Howard L. Snell and Heidi M. Snell, of the Department of Biology and Museum of Southwestern Biology, University of New Mexico, Albuquerque; and Washington Tapia of Galápagos National Park Service, Puerto Ayora, Galápagos Islands.