Detecting 99 million years old spider in mating posture

German scientists found the body of an ancient spider covered with sap and died while mating with females.

According to National Geographic, the spider in the piece of amber found in Myanmar is the first specimen to have a penis in active position, and is the best preserved specimen ever. The ancient spider that existed 99 million years ago named Halitherses grimaldii possesses nearly half the size of the body.

Fossils of the ancient spider protrude below the body.(Photo: Jason Dunlop).

While other spiders and scorpions use modified legs to transfer sperm to females, Halitherses grimaldii puts the penis into the genital hole near the female's mouth. The discovery was published on January 28 in the journal Nature Science.

Scans and 3D images show the characteristic shape of the penis part with the heart-shaped and twisted hooks very different from those of the same family.

Jason Dunlop, the lead author of the study from the Berlin Museum of Natural History, said this piece of amber disturbed scientists because they couldn't find any children inside. Dunlop speculates that the spider may be suddenly removed from the partner or that the penis part is stimulated when the animal struggles before dying.

"Maybe the animal struggles when it gets stuck in the sap. This causes its blood pressure to skyrocket and casually push the protruding penis , " Dunlop said.