A daddy longlegs with a leg span of over 12 inches was discovered in the caves of Laos. Opiliones are an order of arachnids, and are commonly referred to as harvestmen. There are currently 6,500 species of harvestmen worldwide, though the number of extant species may exceed 10,000.
The harvestmen was collected by Peter Jager, an arachnologist at the Senckenberg Research Institute, while he was on a break filming a TV series in Laos’ southern province of Khammouan. The specimen has yet to be identified at a species level. The harvestmen is most likely of the genus Gagrella.
Similarly-sized species of arachnids have been discovered in the surrounding area and have been linked with the cave systems. For now, the exact mechanisms or factors responsible for this frequency of gigantism are yet unclear.
The arthropod limb growth appears to be limited in some fashion, possibly due to the problems of oxygen supply to the extremities or the added difficulty of moving speedily away or towards other creatures.
The basic structure of harvestmen hasn’t changed much in the last 400 million years, as shown by well-preserved fossils from the Devonian period. Although they belong to the taxonomic class Arachnida, they aren’t spiders and belong to the order Opiliones.