Freshwater Aquatic Organism

September 13—Choose a freshwater aquatic organisms other than a fish and answer the following: common and scientific name, physical and behavioral description, primary freshwater habitat, diet, major threats facing it or its environment and why you chose this organism. 

The diving bell spider (Argyroneta aquatica) is the only known spider in the world that lives entirely underwater. 

Like other arachnids, it must breathe air, but it provides its own supply by forming a bubble, which it holds by hairs on its legs and abdomen. The spiders must occasionally return to the surface to replenish their air supply, although some gas exchange happens across the surface of their bubbles, so they don't have to come up very often.

The body of the water spider is densely covered in short hairs that trap air when the spider is submerged, and enables the it to transport air bubbles down to a ‘diving bell’ it constructs from silk. Although the water spider is velvet-grey out of the water, when it is in the water the air trapped around its body gives it a silvery appearance, which has been likened to quick-silver (mercury).

A largely solitary species, the water spider is mainly active at night. Males tend to be more active then females and actively hunt their prey. 

The diving bell spider is found in northern and central Europe and parts of northern Asia. An inhabitant of ponds, slow-moving streams, ditches, and shallow lakes, the water spider favors areas where there is plenty of aquatic vegetation 

The spiders can inflict a painful bite that is often accompanied by feverish symptoms. This is the rare type of species that the males are more often larger than the females and more aggressive. They are carnivorous and prey on aquatic invertebrates, such as water mites, water boatmen, and phantom midge larvae.

They are not endangered or threatened in any way, they have plentiful amounts of places to spend their lifespan in. 

I chose this organism because commonly people don't think of spiders to be a freshwater organism but this is the only type of arachnid that lives solely underwater and can be found in freshwater areas, they are quite scary looking but also very unique in the way that they can form their own oxygen underwater and that the males are actually larger than the females. I'm actually very glad that they are not found much in the United States because they would frighten people! 


Research Sources:
http://en.wikipedia.org/wiki/Diving_bell_spider
http://www.arkive.org/water-spider/argyroneta-aquatica/
http://www.britannica.com/EBchecked/topic/637282/water-spider