Pelican Spiders: Researchers Discover 18 New Assassin Spider Species In Madagascar

Pelican spiders are well-known for their many unusual qualities. Named as such for their uncanny resemblance to pelicans, these arachnids are tiny creatures that are just about as small as a grain of rice, but capable of taking out other spiders with quiet, venomous precision. As such, they are oftentimes alternately known as “assassin spiders.” And while they may seem to be among the most unique arachnids out there, new research suggests that there are close to 30 species of these spiders, making them far more diverse than originally believed.

In a study published Thursday in the journal Zookeys, Smithsonian National Museum of Natural History curator of arachnids and myriapods Hannah Wood and fellow researcher Nikolaj Scharff of the University of Copenhagen detailed their findings, which suggest that Madagascar and South Africa are home to at least 26 separate species of pelican spiders, including 18 from the former country that had yet to be described prior to the publication of the study. According to Wood, there’s a chance that there may be even more species out there that have yet to be discovered and documented.

As explained by a report from Live Science, pelican spiders first existed about 165 million years ago during the Jurassic era, and are recognizable for their fanged pincers. These pincers, which are known as chelicerae, make the creatures look more like birds at certain angles, and when they aren’t hunting, the chelicerae are folded into a long appendage that connects their heads to their bodies. The spiders, however, differ from birds, as their mouths are found at the bottom of their necks, allowing them to be at an ideal range to eat whatever their pincers are able to catch.

Citing the years she spent observing pelican spiders from Madagascar and examples of the species found in museum collections, study lead author Wood noted in the new paper that the creatures are active hunters. While spiders typically focus on spinning their own webs, pelican spiders become active at night as they stalk silk trails from other spiders, moving in a slow and a stealthy motion that usually finds them upside down. The two front legs are responsible for feeling if there are any spiders to prey on, while the six rear legs handle the walking. This is a process that could last for hours, as the creatures are known to wait long periods at the edge of another spider’s web, looking to time their attacks perfectly.

“They wander through the forest at night and they wave their first pair of legs like a pair of large antennae,” Wood explained in a statement quoted by National Geographic.

“They make these big figure-eights with them as they walk, and I think they’re searching for draglines.”

Once they find the right opportunity to strike, pelican spiders quickly impale their prey with their pincers by swinging them away from their bodies at a 90-degree angle. The spiders then hold their prey at arm’s length, waiting until enough venom is pumped into their system before they start feasting.

Although Wood’s study offered some interesting insights into pelican spiders and confirmed that there are almost 20 previously undocumented species out there in Madagascar, there are still some unanswered questions about the peculiar arachnids, specifically regarding their ability to distinguish their fellow pelican spiders from potential prey.

For instance, Wood admitted that she had never witnessed the spiders preying on their own kind, as experiments with multiple examples of the species had seen the creatures mainly “try to give each other space.” She believes there’s a chance that the animals have some sort of immunity to their own venom, or recognize the fact that their protective armor makes it hard for them to stalk each other.