Valves identical, each possessing a raphe (genus is biraphid). Boat shaped in valve view, rectangular in girdle view. Two longitudinal ribs run alongside the raphe from the centre to each end of the valve, where they merge to form an obvious tip. Chloroplasts golden-brown.
Frustulia, Flemming River, X640. Photo: Otago Regional Council & Manaaki Whenua
![[Frustulia], Flemming River, X640. Photo: Otago Regional Council & Manaaki Whenua Image](/assets/Tools-And-Resources/Identification/algae/frustulia__ScaleWidthWzEwMjRd.jpg)