Dwarf spider (Ostearius melanopygius)
Subfamily: Erigoninae (Dwarf Spiders)
Species: O. melanopygius
Binomial name: Ostearius melanopygius
Ostearius melanopygius is a cosmopolitan dwarf spider and is found in many parts of the world. This spider may have first been described from NZ before anywhere else. It is often associated with man-made objects which have allowed it to establish itself in many countries from Europe to Africa, Brazil, Hawaii and Australia and New Zealand.
Its uniformly orange-red abdomen is its most distinctive characteristic. There are no other spiders with a similar appearance. An Ostearius melanopygius male has a 2mm body length which is smaller than the female with a 3mm body length. They have a small web and can be found resting under a great variety of surfaces. They are too small to harm humans.
Visit http://www.bumblebee.org/invertebrates/Araneae.htm for details of a spiders anatomy.
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