A tiny crab just five millimeters long, trapped in amber about 100 million years ago, scientists have discovered. It is the oldest crab ever found, living in the time of the dinosaurs in a wooded area of Southeast Asia.
Usually, in the amber, which comes from the resin of the trees, paleontologists find trapped small animals, mainly insects. But this time they found a crab.
Researchers from the United States, China, Canada, and other countries, led by Javier Luque of Harvard University’s Department of Organic and Evolutionary Biology, who published the journal Science Advances, described the well-preserved caviar with today.
“This is the most complete crab fossil ever discovered. He does not lack a single hair. “Even though it is so small, we managed to see a lot of details,” Luque said.
The discovery of the new fossil sheds new light on the evolution of crabs and their spread on Earth. The first sea crab fossils date back at least 200 million years. Previously scarce and poorly preserved non-marine fossils had led scientists to estimate that the first non-marine crabs came ashore 50 to 75 million years ago.
But the new discovery takes this development far back in time, at least 100 million years ago. It is estimated that at least 12 times different species of crabs evolved independently to live outside their former marine environment, conquering the land. Today, crabs are everywhere, from the depths of the oceans and coral reefs to beaches, rivers, caves, and even trees. It is one of the few species of animals that have managed to conquer the sea, freshwater and land. Their gills evolved to include tissues such as the lungs, which allowed them to breathe both in and out of the water.
The new fossil, named “Cretapsara athanata” and now housed in the Longyin Amber Museum in Chinese Yunnan, was found in a jungle in northern Myanmar in 2015, but only recently has it been studied extensively by scientists. Among other things, he was found to have only well-developed gills, so he was probably a freshwater crab, but he probably made short trips ashore, where at some point he was trapped in amber.
As Luque said, “Crabs are found all over the world, they are extremely tasty for those who eat them, they honor them in parades and celebrations, they even have their own constellation. They are generally charming and some have an extremely strange appearance. Their diversity has sparked the imagination of scientists and the public. “Our discovery is indeed a great moment for crabs!”