Vital statistics
Attributes Multiple eyes; two sharp pincers; size of a human head; lived in burrows; used digestive juices to kill
Diet Petrolacosaurus; smaller arthropods and reptiles
Fossil finds North America
Temporal fossil range Carboniferous
Other names Megarachne
Production information
Notable individuals
TV appearances Walking with Monsters: Water Dwellers
Walking with Monsters: Reptile's Beginnings
Book appearances
But as they move in land, they'll face an ancient enemy; more deadly than ever before The arthropods are back!

Mesothelae was a solifugid arachnid from the Carboniferous. It was a giant spider the size of a human head.

Physical appearance and biologyEdit

Mesothelae spiders had two, large pincers that were shaped like fangs which could excrete digestive juices. It also had several, black eyes positioned on the top of its head. The majority of its body was black and the abdomen and the base of the pincers were bright red.

Behaviour and traitsEdit

Mesothelae spiders were large arachnids the size of the head of a human. If this animal was alive today, it would be hunting cats. During its time, it hunted primitive reptiles like Petrolacosaurus as well as smaller arthropods. It killed its prey by stabbing it with its fang-like pincers and then injecting it with digestive juices.

Like modern spiders, Mesothelae could spin webs. They mainly spun webs to aid in creating a burrow (or headquarters). They would spin a web that would act as a tripwire outside the burrow. The Mesothelae inside would detect the vibrations from its headquarters and would ambush the intruder.

These headquarters were commonly situated in neighbourhoods; with many burrows in a single areas. However, the Mesothelae inside each individual hole would be aggressive to one another and would often attack any passerby's. The burrows were often targets for lightning bolts.

In Walking with MonstersEdit

Water DwellersEdit

A Mesothelae crawled up to a Petrolacosaurus nest and killed most of the juveniles within it.

Reptile's BeginningsEdit

A female Mesothelae was hiding in some bushes before retreating to her burrow. She then carefully positioned herself on her tripwires to detect intruders. As doing so, an adult Petrolacosaurus approached her headquarters. As it got closer, the Mesothelae came out of its burrow and chased the reptile. However, the Petrolacosaurus managed to escape by hiding in a fallen log. The Mesothelae appeared to have left but as the Petrolacosaurus backed further into the log, the Mesothelae broke through the ceiling and attacked the reptile. Using her pincers, she managed to kill the Petrolacosaurus.

As she dragged her prize back to her headquarters, she realized that the burrow had flooded and evacuated. In search of a new hole to adapt, the Petrolacosaurus she recently killed was snatched by the monster dragonfly Meganeura, who flew away to the forest canopy with it.

Soon after, the Mesothelae came to a lake but was scared off by a group of Proterogyrinus. She then entered a neighbourhood of Mesothelae but as she passed by, the resident spiders didn't tolerate her presence. As she tried to find a new hole, she accidentally disturbed a male Arthropleura.

Later, as a storm approached, the Mesothelae found a hole which contained a Petrolacosaurus. The spider evicted the residing reptile and modified the burrow for her needs. At night, she had completed her headquarters and tested the tripwires. It was already picking up vibrations but it was from the approaching storm. As the storm arrived, a lightning bolt struck her burrow.

The next day, an inquisitive Petrolacosaurus approached ground zero and investigated the Mesothelae burrow. When it exited, he came out dragging the fried corpse of the Mesothelae, which was instantly killed by the lightning. The reptile then feasted on a Mesothelae barbeque.

Behind the scenesEdit

The design of the Mesothelae in Walking with Monsters was based on Megarachne, which at the time of production was identified as a giant spider. However, during late production, scientists reclassified Megarachne as a sea scorpion so the production staff had no time to redesign the animal and instead replaced its name with Mesothelae.[1]

List of appearancesEdit

Paleontological inaccuraciesEdit

  • No Mesothelae spider was ever that large.

Notes and referencesEdit