"Two and a half" new species of leaf-toed geckos have been discovered in Galápagos
A group of scientists led by Tropical Herping (TH), Universidad San Francisco de Quito (GSC-USFQ), and the Galápagos National Park Directorate (PNG) announced the discovery of "two and a half" new volcanic-rock-dwelling geckos in the Galápagos Islands. The study was published today in the book: Reptiles of the Galápagos.
One of the new species, the Andy Sabin's Leaf-toed Gecko (Phyllodactylus andysabini), was discovered around Wolf Volcano on northern Isabela Island. Photo by Lucas Bustamante.
Two of the geckos are completely new species discovered on the volcanoes of Isabela Island, whereas the remaining gecko is not actually a full new species... but sort of a "half new" species. It is actually a subspecies discovered in 1973 that was never given full species status, probably because detailed genetic analyses were not available at the time, but now, thanks to the use of modern genetics, this "half species" has now been brought back into the spotlight by being granted full-species status. In scientific terms, the species' name has been "resurrected."
See this video of the new species by Jorge Castillo.
"Galápagos may be the most studied archipelago worldwide, but it keeps surprising us with new species," says Jorge Carrión, Director of the Galápagos National Park and co-author of the study. "To those of us who are in charge of managing protected areas, the discovery of these new gecko species is a wonderful news, since it gives the national park the tools needed to more accurately manage and protect biodiversity.”
This is the DNA evolutionary tree that the researchers used to identify the new species and show their relationships with other Galápagos leaf-toed geckos. The new (and "half new") species are: Phyllodactylus andysabini ■, P. maresi ■, and P. simpsoni ■. Graphic by Alejandro Arteaga. Photos by Tropical Herping.
Distribution of the new species of leaf-toed geckos in Galápagos. Map by Alejandro Arteaga and Lorena Benitez.
With the financial support of many organizations (most notably Andy Sabin Family Foundation, Fundación Jocotoco, Galápagos Conservancy, Galapagos Science Center, and Minifund) the team of researchers and park rangers conducted expeditions to Marchena Island and to the volcanoes of northern Isabela Island (Wolf and Darwin volcanoes) on February 2019. These expeditions led to the discovery of the new species.
The researchers explored the summit of Wolf Volcano, in northern Isabela Island. Photo by Lucas Bustamante.
"The volcanoes where the new gecko species live are some of the most remote and geologically active volcanoes in the world," says Alejandro Arteaga, co-founder of Tropical Herping and lead author of the study. "One of the species, the Andy Sabin Leaf-toed Gecko (Phyllodactylus andysabini), is actually considered to be facing a high risk of extinction in the near future due to the combined effects of volcanic activity and predation by cats and black rats.”
Wolf Volcano is in constant activity, with its last eruption recorded on May 2015. Photo by Lucas Bustamante.
In order to confirm these geckos as new species, the biologists obtained research permits to collect tissue samples from the tip of the tail of geckos. These samples were sequenced at Universidad San Francisco de Quito (USFQ). After analyzing the samples, the scientists realized that there were at least two undescribed species of geckos living on Isabela Island. The genetic studies also showed, quite surprisingly, that Marchena Island was inhabited by the same species of gecko living on Santiago Island (it is odd that a terrestrial species inhabits two completely different volcanic islands!).
"One of the most puzzling aspects about the biology of the new geckos is that the two new species evolved from the same common ancestor and on the same island," explains Jose Vieira, co-author of the study, "and one of them occurs as high as 1,515 m above sea level. No other Galápagos gecko occurs at a higher elevation."
The Mares Leaf-toed Gecko (Phyllodactylus maresi), previously considered a subspecies, was elevated to full-species status. Photo by Jose Vieira.
"The process of describing a new species of reptile in Galápagos cannot just be based on the animal's appearance," says Lucas Bustamante, co-author of the study and co-founder of Tropical Herping." It has be based on genetic data, which helps determine whether a species is new to science, the process by which its ancestors colonized the archipelago, and the relationships between the species and its closest relatives. Solving the mysteries of complex ecosystems requiere complex projects, big funding, and solid research groups.”
The researchers and park rangers spent a total of 20 days searching for the new species of geckos in uninhabited parts of Galápagos. Photo by Lucas Bustamante.
The new species of geckos were named by two conservation organizations in honor of their conservation heroes. Global Wildlife Conservation chose to name one of the new geckos Phyllodactylus andysabini to honor Andrew Sabin, also known as Andy or "Mr. Salamander," in recognition for his life-long support of environmental programs around the world, as well as for his passion for the preservation of amphibians and reptiles. Fundación Jocotoco chose to name the other gecko P. simpsoni, honoring Dr. Nigel Simpson for his long-standing and visionary leadership in conservation.
The two new geckos that inhabit Isabela Island can be distinguished from each other based on the color of their throats. (a) Phyllodactylus andysabini has a brown-stippled throat. (b) Phyllodactylus simpsoni has an immaculate throat. Photos by Jose Vieira.
"Naming species is at the core of biology”, says Dr. Juan Manuel Guayasamin, co-author of the study and a professor at GSC-USFQ in Ecuador. "Not a single study is really complete if it is not attached to the name of the species, and most species that share the planet with us are not described.”
The official description of these new geckos was published in a book (the Reptiles of the Galápagos book) rather than in a scientific journal. The book does not only include the description of the new geckos, but also information about every single one of Galápagos' 58 reptile species. "Publishing a book of this magnitude is gargantuan task, says Alejandro. "It took more than two years of intense fieldwork, one year of office work, and the financial and logistic support of 22 organizations.”
Juan Manuel also emphasizes that: "the book and the new species' descriptions exemplify how research and governmental institutions can overcome bureaucratic, logistic, and financial constraints when working for common educational and conservation goals."
"At the end of the day, discoveries like these are not just useful to scientists,” says Lucas, "they are meant to help improve local people’s livelihoods! If locals live in better-studied places, it is easier for them to understand the resources they really have, how to love and interact positively with them, and realize what they can lose if they don't protect them.”
Mares Leaf-toed Gecko (Phyllodactylus maresi). Photo by Jose Vieira.