Phalangium opilio

Phalangium opilio
Male Phalangium opilio
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Arachnida
Order:	Opiliones
Family:	Phalangiidae
Genus:	Phalangium
Species:	P. opilio
Binomial name
Phalangium opilio Linnaeus, 1758

Phalangium opilio is "the most widespread species of harvestman in the world", occurring natively in Europe, and much of Asia. The species has been introduced to North America, North Africa and New Zealand. It is found in a wide range of habitats, including meadows, bogs, forests, and various types of anthropogenic habitats, such as gardens, fields, hedgerows, lawns, quarries, green places in built-up areas, walls and bridges. Phalangium opilio is known to feed on Helicoverpa zea eggs, and thus can act as biological pest control for soybean crops. The species is nocturnal, as is typical of opilionids.

Description

Females have a body length of 6–9 mm (1⁄4–3⁄8 in), males are slightly smaller at 4–7 mm (3⁄16–1⁄4 in). Males however have longer legs; the second leg is about 54 mm (2+1⁄4 in) in males and 38 mm (1+1⁄2 in) in females. Males and females are similarly coloured and marked, although males' markings tend to be less clear. The body has a three-lobed darker "saddle", usually with spots or dashes in the midline. Mitopus morio has a very similar appearance, but P. opilio can be distinguished by the two pale "denticles" (small teeth-like structures) below the anterior margin of the carapace. Males have long forward-pointing "horns" on the second segment of their chelicerae.

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  Female
• 
  Male with Trombidium sp.'; note the "horns" on the chelicerae
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  Female side view
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  Female bottom with a Trombidiformes mite
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  Female