Length 3-5mm. Bluish-green ("glaucous") or greenish-yellow planthopper.  Females are easier to identify than males, by examination of external genitalia.

other Chloriona

Unless identified by a recognised expert, a photo is required and the specimen should be examined with a microscope. In the comments box, state the key or ID method used and describe the size and identifying characters.

Reedbeds, on Common Reed.

Widespread but localized. 

Unknown.