Museum graduate student Edward Stanley recently used high-resolution x-ray images of tiny “armor” bones to help an international team of scientists discover a new species of lizard from remote, war-torn mountains in Central Africa. The lizard, Cordylus marunguensis, was found on the Marungu Plateau in the southeastern Democratic Republic of the Congo. It is described in the African Journal of Herpetology.
The new lizard was discovered on an expedition led by Eli Greenbaum, assistant professor of evolutionary genetics at the University of Texas at El Paso, and Chifundera Kusamba, a research scientist from the Centre de Recherche en Sciences Naturelles in the Congo. Suspecting that the lizard represented a new species, Greenbaum sent DNA samples and a specimen to Stanley, a third-year student in the Museum’s Richard Gilder Graduate School—the first museum program in the Western Hemisphere with the authority to grant the Ph.D. degree.
Stanley compared the DNA of the Marungu lizard to similar species throughout Africa and confirmed that it was a new species. He bolstered the finding by using a technique called high-resolution x-ray computed tomography (CT) in the Museum’s Microscopy and Imaging Facility. The CT scans reconstructed the lizard’s skeleton in three dimensions, the first time such a technique has been used to describe an existing lizard species.
“CT data has been included in the descriptions of a number of living fish and invertebrate species as well as many extinct species, but to our knowledge, this is the first time it’s been used for an extant lizard,” Stanley said. “Including a digital reconstruction as a part of the species description gives researchers an enormous amount of detailed data about this important specimen.”
The CT scan confirmed the presence of tiny bones called osteoderms in the heavily armored scales of the new species. The reinforced scales are thought to protect the lizards from attacks by predators, and in some cases, to allow the animals to avoid attacks by wedging themselves between small, rocky crevices.
Stanley found that the new lizard has significantly fewer osteoderms on its belly than is seen in its closest genetic relative. He is on a mission to take full-body CT scans of the more than 80 species in the lizard’s family to help facilitate future study of the animals.
Read the full article in the African Journal of Herpetology.