1) Arthropod family 2) Family corixidae 3) Water bugs 
Corixidae is a family of aquatic insects in the order Hemiptera that inhabit ponds and slow moving streams, where they swim near the bottom. There are about 500 known species worldwide, in 33 genera, including the genus Sigara. Members of the Corixidae are known in the United States as water boatmen, a term that is sometimes used in the United Kin...
[n] - water bugs
family Corixidae noun water bugs