New species of prehistoric mosquito found in museum amber

Aug. 30 () –

A 40-million-year-old piece of Baltic amber found in the 1960s by a Danish collector contains the first fossil of a fungus-eating mosquito belonging to a rare genus.

The new discovery provides new insights into the distribution of mosquito species and biodiversity in space and time, according to the article published in the journal Scientific Reports.

At that time, Europe’s climate was warmer and wetter, which provided favourable conditions for mosquitoes, among other things. One such mosquito, which died trapped in a piece of pine resin, has given researchers at the Natural History Museum of Denmark the opportunity to add a new dimension to the story. new species of prehistoric mosquito to his insect family.

For decades, the piece had been hidden in the museum’s 70,000-piece amber collection. Recently, it was retrieved from the drawers and subjected to a thorough examination by a team of Polish entomologists. The insect specialists were able to identify the mosquito as an extinct species of a rare genus of predatory mosquitoes. Today, living species of the genus are found only in Hokkaido, Japan, and California.

“This is the first time that a fossil mosquito of this genus has been found, which was thought to only live in Japan and North America. The discovery shows that this type of mosquito was also widespread in Europe in past climates and gives us new insights into its distribution on Earth,” he explains. in a statement Alicja Pelczynska, a PhD student at the University of Lódz and the University of Copenhagen, who led the description of the mosquito.

Researchers believe the ancient mosquito is a species of “missing link” connecting its two rare, still-living relatives in Japan and the United States. The land distance between the living species has puzzled researchers, but the new fossil shows the species’ route may have spanned the European continent.

“Until now, the distribution of this genus of mosquitoes has been strange, with many thousands of kilometers between species.“So it makes sense that it was found in Europe, which is roughly halfway between Japan and North America,” Pelczynska says.

To learn more about the mosquito buried in amber, the researchers began by polishing the piece of amber, which had been covered by the sea and the sun, until it became shiny and transparent.

Once clear, they used an advanced camera and spectrometer to take a chemical fingerprint of the amber. This confirmed that the piece is Baltic amber. They then examined the fossil and determined the species of the insect. This part of the process was carried out by closely studying the males’ genitalia, where identifying characteristics often vary.

“Insects mate end-to-end, which places certain demands on their genitals. The male has appendages, or pincers, next to the actual penis, which he uses to grasp the female mosquito during mating. We use the shape of these tweezers to identify it“explains Lars Vilhelmsen, associate professor and curator at the Natural History Museum of Denmark.

Based on their analysis, the researchers estimate that the mosquito was buzzing around in the vast pine forests of what we now know as Scandinavia around 35-40 million years ago. The mosquito became trapped in a piece of tree resin, which was carried to the North Sea by rivers, ocean currents and glaciers of the last ice age.

“An amber collector named CV Henningsen found the piece of amber on the west coast of Jutland in the 1960s. Henningsen sold the piece, along with the rest of his collection, to the Natural History Museum of Denmark. Since the mosquito species had never been described before, We named it after him and it is now known as Robsonomyia henningseni“, says Vilhelmsen.

Amber is an exceptional natural time capsule for scientists. With its protective lamination, it preserves ancient insect and plant remains and allows us to learn what the Earth was like up to 230 million years ago. But if it is released from its amber casing, the insect will disappear.

According to Vilhelmsen, there is no blood or DNA to suck from mosquitoes to somehow reanimate them, as done in the Jurassic Park movies.

“Virtually all of the mosquito’s organic material has long since decomposed, turning it into a hollow shell. If you try to remove it from the amber, it falls apart. So the best we can do is study it inside the amber. Insects trapped in amber “can be studied almost as accurately as their living relatives.”