Alligatorweed Flea Beetle (Agasicles hygrophila), native to Brazil, was released in California and all southeastern coastal states in 1964 to control the spread of the exotic invasive plant Alternanthera philoxeroides which many kayakers know as Alligatorweed.
The Alligatorweed Flea Beetle has enlarged upper leg sections on their hind legs which allow them to jump a long distance if disturbed, hence the common name, "Flea Beetle." Kayaking into a thicket of alligatorweed when the beetles are active will result in beetles jumping everywhere, including onto your clothing and kayak. Not to worry, the beetles do not bite.
Alligator Flea Beetle eggs are laid on the bottom of alligatorweed leaves so larvae will have abundant food when they hatch. Mature larvae burrow into and pupate in the hollow stems of the alligatorweed plant and emerge as adults through the holes in the stems.
Source: http://www.sms.si.edu/irlspec/agasicles_hygrophila.htm