Paleontologists working in the Caribbean have uncovered the first-ever salamander preserved in amber. It’s a discovery that’s shedding light not just on salamander evolution, but the ancient geology of the Caribbean itself.
“I was shocked when I first saw it in amber,” noted George Poinar, Jr., a professor emeritus in the Orgeon State University College of Science, in a statement. A co-author of the study, Poinar is an expert in the study of creatures caught in amber.
“There are very few salamander fossils of any type, and no one has ever found a salamander preserved in amber,” he says, “finding it in Dominican amber was especially unexpected, because today no salamanders, even living ones, have ever been found in that region.”
The fossil was discovered in an amber mine located in the northern mountain range of the Dominican Republic.
The newly described salamander, now dubbed Palaeoplethodon hispaniolae, featured back and front legs, but lacking in distinct toes. The salamander’s webbing suggests it wasn’t a prolific climber, so it probably preferred to dwell in small trees or tropical flowering plants. The full description of Palaeoplethodon, which may have lived as far back as 40 to 60 million years ago, can now be found (pdf) in the journal Palaeodiversity.
The researchers aren’t sure why salamanders no longer exist in the Caribbean, but they suspect it was on account of climate change or a particularly prolific predator. Interestingly, the physical evidence suggests that an early lineage of phethodon salamanders evolved in tropical America—a time when the Proto-Greater Antilles, which now includes the islands of Cuba, Jamaica, Puerto Rico, and Hispaniola, were still joined to North America. This means the salamanders must have remained in these areas as they turned into islands. Either that or they crossed a land bridge, or rode in on floating debris.
Fascinatingly, the preserved salamander appears to have come to an untimely demise. Analysis of the fossil suggests it had a leg bitten off during an encounter with a predator, and during the confusion, fell into a gooey resin deposit, allowing it to be preserved in amber.
Read the entire study at Palaeodiversity: “Palaeoplethodon hispaniolae gen. n., sp. n. (Amphibia: Caudata), a fossil salamander from the Caribbean.”
Email the author at firstname.lastname@example.org and follow him at @dvorsky. All images Ponar & Wake, 2015/Palaeodiversity/Oregon State University