Scientists discover rare fossils of spiders 110 million years old, with strange and shining eyes

An amateur fossil hunter was inspecting a shale site in South Korea when he discovered something attractive.

A spider specimen with strangely brilliant eyes has been preserved in the rock formation and, according to a team of researchers, dates back to 113 million years ago.

Their results are published in an article in the Journal of Systematic Palaeontology and were hailed as the first time that the tapetum, an anatomical feature that allows spiders to have reflective eyes, was found in a fossil.

Scroll for the video

An amateur fossil hunter has discovered a mysterious spider specimen with strangely brilliant eyes (photo), preserved in South Korean shale and whose date of birth is 113 million years old.

It is also said that it is the first time that researchers discover this family of spiders, lagonomégopides, apart from amber.

Paul Selden, director of the Institute of Paleontology at the University of Kansas, Tae-Yoon Park of the Korean Polar Research Institute and amateur fossil researcher and Korean high school student, Kye-Soo Nam, discovered spiders in shale discovered, discovered during a construction project.

Spiders and other insects are often found in amber, not fossilized in rock, as their soft bodies do not keep well with time.

They were astonished to find the preserved lagonomegopids in a 112-million-year-old Cretaceous-era rock near the town of Jinju in South Korea.

"Because these spiders were preserved in strange mottled spots on a dark rock, what was immediately obvious was their large eyes brightly marked with crescent-shaped lines," explained Selden.

For the first time, researchers have discovered a family of spiders, lagonomegopids, fossilized in rock (photo). Soft-bodied insects such as spiders are in amber tones

The rock dating back to the Cretaceous era, 112 million years old, located near the city of Jinju in South Korea, helped protect spiders. The shale was being excavated as part of a construction project

The fossils have allowed scientists to understand with remarkable accuracy how this family of spiders has been able to survive between 110 and 113 million years ago.

Scientists believe that the reflective tapetum in the spiders' eyes helped them to hunt at night.

"This opens up a whole new world in terms of how these things lived and how they would have caught their prey," Selden told Gizmodo.

The tapetum is a reflective structure located behind the eye where light enters and is returned to the retina, Selden noted.

Lagonomegopids are not the only family of spiders to have reflective eyes – wolf spiders also have them, in addition to other types.

Scientists' discoveries mark the first time that the tapetum (right), an anatomical feature allowing spiders to have reflective eyes, was found in a fossil or preserved outside of amber. On the photo (left), a lagoongopid aged 99 million years old preserved in an amber wrap

Other animals, such as cats, have tapetums, which is why their eyes look like lasers under certain spotlights or when they are captured by a camera flash.

The lagonomegopids had "canoe-shaped" tapetas, helping the researchers to distinguish them from the other 10 specimens of spiders found in shales.

"It's an extinct spider family that was clearly very common in the Cretaceous and occupied niches now occupied by jumping spiders that have not evolved before," explained Selden.

"But these spiders did things differently. Their eye structure is different from that of jumping spiders.

"It's nice to have exceptionally well-preserved features of internal anatomy, such as eye structure. It's really not often that something like this is kept in a fossil, "he added.