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Opiliones (harvestmen)
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Opiliones are commonly called shepherd spiders,
harvest spiders or harvestmen. 'Opilio' in Latin means shepherd and the name is
probably derived from the fact that in earlier times, European shepherds
sometimes walked on stilts to observe their flocks better and Opiliones look as
if they are on stilts when walking. The term harvestmen or harvest spiders was a
result of them being seen only during harvesting time. They are also referred to
as daddy long legs but should not be confused with similarly named spiders, the Pholcidae.
Opiliones are not spiders and have no spinning organs, fangs or venom glands and are
harmless to man.
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Opiliones (body about 5 mm). [image N.
Larsen ©] |
Opiliones are not well known as they and rarely seen due to
their cryptic lifestyle. They live in damp forest areas under leaf-litter where
they feed on small insects and other invertebrates, snails, fungi and dead
animal and vegetable matter. They are more numerous at sea level and numbers
diminish with altitude.
The head and thorax are not separated by narrow
constriction as with spiders. They have round bulbous bodies and very long legs
and generally small (bodies up to about 7 mm long). Their cryptic colouration
affords protection from predators but should they be attacked, they are usually
able to repel the attacker with a repugnant secretion from odiferous glands.
References
- Lawrence, R. F. 1981. South African Harvest
Spiders. The Naturalist. 25(3): 13-27.
Links
Text by Norman Larsen ©. |
