365NEWSX
365NEWSX
Subscribe

Welcome

First Dinosaur Era Crab Discovered – Fully Preserved in 100-Million-Year-Old Amber - SciTechDaily

First Dinosaur Era Crab Discovered – Fully Preserved in 100-Million-Year-Old Amber - SciTechDaily

First Dinosaur Era Crab Discovered – Fully Preserved in 100-Million-Year-Old Amber - SciTechDaily
Oct 24, 2021 2 mins, 27 secs

Credit: Artwork by Franz Anthony, courtesy of Javier Luque (Harvard University).

The most common fossils found in amber, which is formed from resin exuded from tree bark, are land-dwelling animals, mainly insects.

In a study published on October 20, 2021, in Science Advances an international team of researchers describe the first crab from the Cretaceous dinosaur era preserved in amber.

The study used micro CT to examine and describe Cretapsara athanata, the oldest modern-looking crab (approximately 100 million years old) and the most complete fossil crab ever discovered.

Both Cretapsara and Callichimaera are new branches in the crab tree of life that lived during the Cretaceous Crab Revolution, a period when crabs diversified worldwide and the first modern groups originated while many others disappeared.

Cretapsara athanata: The first crab in amber from the dinosaur era.

Unfortunately, fossils of nonmarine crabs are sparse and largely restricted to bits and pieces of the animals carapace – claws and legs found in sedimentary rocks.

It’s absolutely complete and is not missing a single hair on the body, which is remarkable,” said lead author Javier Luque, postdoctoral researcher in the Department of Organismic and Evolutionary Biology, Harvard University.

athanata Luque gen.

Credit: Images and figure by Elizabeth Clark and Javier Luque.

Yet, the animal was entombed in Cretaceous amber and the presence of well-developed gills indicated an aquatic to semi-aquatic animal.

Aquatic animals are rarely preserved in tree resins that become amberC

How then, the researchers asked, did a 100 million year old aquatic animal become preserved in tree amber, which normally houses land-dwelling specimens.

athanata Luque gen.

(A) Whole amber sample with crab inclusion in ventral view.

(C) Whole amber sample with crab inclusion in dorsal view.

“In the fossil record, nonmarine crabs evolved 50 million years ago, but this animal is twice that age.”.

Cretapsara bridges the gap in the fossil record and confirms that crabs actually invaded land and fresh water during the dinosaur era, not during the mammal era, pushing the evolution of nonmarine crabs much further back in time.

They further hypothesize that like the crabs found in amber from the Miocene, Cretapsara could have been a tree climber.

“These Miocene crabs are truly modern looking crabs and, as their extant relatives, they live in trees in little ponds of water,” said Luque, “these arboreal crabs can get trapped in tree resin today, but would it explain why Cretapsara is preserved in amber?”.

The researchers chose the name Cretapsara athanata, which means the immortal Cretaceous spirit of the clouds and waters, to honor the Cretaceous, during which this crab lived, and Apsara, a spirit of the clouds and waters in South and Southeast Asian mythology.

For more on this research, read Researchers Discover First Dinosaur Era Crab Fully Preserved in 100-Million-Year-Old Amber.

Reference: “Crab in amber reveals an early colonization of non-marine environments during the Cretaceous” by Javier Luque, Lida Xing, Derek E.

Summarized by 365NEWSX ROBOTS

RECENT NEWS

SUBSCRIBE

Get monthly updates and free resources.

CONNECT WITH US

© Copyright 2024 365NEWSX - All RIGHTS RESERVED