Biology

This harvestman is nocturnal and fairly active, walking raised up on its long legs (1) (3) (6). Indeed, the order name 'Opiliones' comes from the Latin word 'opilio' meaning 'shepherd', because walking harvestmen resembled the European shepherds who used to walk on stilts for an improved view of their flock. It is omnivorous, feeding commonly on small insects, plant material and fungi (1). The first pair of appendages (chelicera) near the mouth collects the food items and passes them to the second pair of appendages (pedipalps) where they are held and crushed by microscopic claws at the end of the pedipalps (4) (7). The food is chewed and ingested, rather than having the juices sucked out (2). The harvestman cannot live for long without water (4). Harvestmen are most commonly seen in autumn, particularly during harvesting time (6) (7). They are often found on shady walls on the outside of buildings, where they cluster together in groups of up to 400 (8). They rest flat on the walls with their legs entwined, which serves several possible functions. By gathering together, the harvestmen may be creating an area of desirable temperature and humidity, or making use of the collective repellent power of their smelly defence (2). It has also been suggested that these aggregations pulsate in order to appear more intimidating to their predators (2). Harvestmen mate by internal fertilisation, and females use their ovipositor to lay the already fertilised eggs into crevices in the soil (5). The eggs survive through the winter and hatch in spring (7).