''Rhagovelia'' is a genus of smaller water striders in the family

Veliidae Veliidae is a family (biology), family of gregarious predatory insects in the suborder Heteroptera. They are commonly known as riffle bugs, small water striders, or broad-shouldered water striders because the segment immediately behind the head ...

. There are at least 390 described species in ''Rhagovelia''. File:Rhagovelia whirling in a swarm.webm, Rhagovelia can be gregarious and form swarms.

Morton Arboretum The Morton Arboretum, in Lisle, Illinois, United States, is a public garden and outdoor museum with a library, herbarium, and program in tree research including the Center for Tree Science. Its grounds, covering 1,700 acres (6.9 square kilometre ...

Illinois Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its ...

Evolution

Origins

The origins of the genus are among water striders of Veliidae family without propelling fans on their legs.

Evolution from water striders

Genes 'geisha' and 'mother-of-geisha'

The duplication of genes, called by researchers 'geisha' and 'mother-of-geisha', caused evolutionary creation of propelling fans on middle pair of water strider's legs which in its turn has made able for species in the genus to walk across more fast-flowing and turbulent streams.

References

External links