Harvestman The Biology Of Opiliones Anatomy

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Harvestmen: The Biology Of Opiliones

A harvestman (a male Phalangium opilio), showing the almost fused arrangement of abdomen and cephalothorax that distinguishes these arachnids from. The Harvestmen are eight-legged.

Although they belong to the class of, harvestmen are not. They belong to the Opiliones or Phalangids. More than 6,400 species of harvestmen have been discovered, although the real number of species may exceed 10,000. Well-preserved have been found in the 400-million year old of. The samples found look surprisingly modern. Apparently, the basic structure of the harvestmen has not changed much since then.

In some places, harvestmen are known by the name 'daddy longlegs', but this name is also used for two other unrelated arthropods: the ( Tipulidae) and the ( Pholcidae). Many species are, they eat anything they can find. Most of the time this is small, and some and. Harvestmen are not dangerous to humans. None of the described species has poison glands. They are not 'true' spiders even though they look like spiders in many ways. Nokia C1 Mobile Internet Software. For example, harvestmen have no venom or silk glands; spiders have these.

Contents • • • • Anatomy These arachnids have exceptionally long walking legs, compared to body size, although there are also short-legged species. In harvestmen the two main body sections (the abdomen and cephalothorax) are broadly joined, so that they appear to be one oval structure; they also have no venom or silk glands, unlike true spiders. In more advanced species, the first five abdominal segments are often fused into a dorsal shield called the scutum, which is normally fused with the carapace. In some species, this shield is only present in males. The second pair of legs is longer than the others and works as antennae. This can be hard to see in short-legged species.

Harvestman anatomy. Fumontana is a genus of harvestman that occurs in the United States. & Giribet, G. (eds.) (2007): Harvestmen - The Biology of Opiliones.

The feeding apparatus (Stomotheca) differs from other arachnids as they are able to eat their food in chunks, without needing to liquefy it. Most species have a single pair of eyes in the middle of their heads, oriented horizontally.

However, there are some eyeless species. Further reading • (2005) • Pinto-da-Rocha R. Harvestmen – the biology of Opiliones. Harvard University Press • Pinto-da-Rocha R. Third species of Guasiniidae (Opiliones, Laniatores) with comments on familial relationships.

Journal of Arachnology 31: 394-399. • Shultz, Jeffrey W. Phylogeny of Opiliones (Arachnida): an assessment of the 'Cyphopalpatores' concept. Journal of Arachnology 26: 257-272. Other websites.

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