This month a giant harvestman has been found in a cave in Laos by Dr. Peter Jäger of the Senckenberg institute. They have not yet been able to identify it to the species level, but it probably is a member of the genus Gagrella in the Sclerosomatidae family.
While the body of this harvestman is not even 1 cm in length, the legs have a span of 33 cm. That means there is only one harvestman ever found that is larger: a species from Brazil with a span of 34 cm. (Unfortunately I can’t find out which species. Do you know? Please leave me a message!)
The interesting thing is that also other invertebrates reach giant dimensions in those caves in Laos, for example the Laotian huntsman spider Heteropoda maxima (span 30 cm), the whip scorpion Typopeltis magnificus (span 26 cm) and the predatory centipede Thereuopoda longicornis (40 cm). The reason why ‘giantism’ has developed there is still unclear. It is expected however that the invertebrates cannot become much larger than this. Either the oxygen supply would become a problem, or, in the case of harvestmen, the legs would become too long for fast movement.