Length 3 mm.  Macropterous (long-winged) and brachypterous (short-winged) forms occur, and colouration varies.  Males are darker than females.  Forewings are translucent, and may be tinged brown or whitish; in macropters they are considerably longer than abdomen.

Javesella is a difficult genus, and care is needed to separate species. Females are difficut to ID.  Long-winged forms of Muellerianella have a broad central pale area on pronotum and scutellum

Dissection of male genitalia is advised for verification.  Good quality photos of a specimen from top down will support ID, plus detailed photographs of genital segment of male from top/side/rear.  Note habitat and host-plant.

Grassland.

Adult: April to October.

Common (ref.: UK Auchenorrhyncha checklist 2021)

Frequent

https://www.britishbugs.org.uk/homoptera/Delphacidae/Javesella_pellucida.html