A giant tarantula has been filmed dragging a young opossum away to its death in what is thought to be the first ever documentation of a spider preying on these small marsupials.
In footage released by the University of Michigan, the huge spider—estimated to be around the size of a dinner plate—can be seen on top of the young mouse opossum, which was about the size of a softball.
"The opossum had already been grasped by the tarantula and was still struggling weakly at that point, but after about 30 seconds it stopped kicking," biologist Michael Grundler said in a statement. "We were pretty ecstatic and shocked, and we couldn't really believe what we were seeing. We knew we were witnessing something pretty special, but we weren't aware that it was the first observation until after the fact."
The team, led by evolutionary biologist Daniel Rabosky, was studying predator-prey interactions in the Amazon rainforest. To do this, they carried out night surveys by walking through the forest with flashlights and headlamps and scanning the foliage for signs of activity. One night, they heard "some scrabbling in the leaf litter." When they illuminated the ground where the rustling was coming from, they saw the spider and opossum.
After reviewing the footage, an expert at the American Museum of Natural History confirmed it was the first documentation of a spider preying on an opossum.
During the research trip—to the Amazon's Madre de Dios region of southeastern Peru—the team also captured spiders preying on frogs, lizards, snakes and fish. Their findings have been published in the journal Amphibian & Reptile Conservation. Images from the trip show different species of spider and their meals.
Spiders are extremely diverse predators and they are known to eat creatures from all the major vertebrate groups, including birds, mammals, reptiles and fish. They tend to have body parts that are specialized for hunting, such as venom, modified jaws and huge fangs.
As well as spider attacks, the team also documented centipedes feasting on vertebrates. In one case the team saw a large scolopendrid centipede eating a dead coral snake. Study co-author Joanna Larson said: "Coral snakes are very dangerous and can kill humans. To see one taken down by an arthropod was very surprising. Those centipedes are terrifying animals, actually."
Rabosky said they had discovered an "underappreciated source of mortality among vertebrates" in the rainforest. "A surprising amount of death of small vertebrates in the Amazon is likely due to arthropods such as big spiders and centipedes," he said.