Diagnostic features
Pennate diatom, valves boat-shaped in valve view, cruciform (cross-like) or with an undulate outline in some species; rectangular in girdle view. Valves identical, neither possessing a raphe (genus is araphid). Striae do not meet in centre of the valve, where there is a thickened central sternum. Chloroplasts golden brown.
![[Staurosira], X1000. Photo: Phil Novis, Manaaki Whenua Image](/assets/Tools-And-Resources/Identification/algae/staurosira_phil1000__ScaleWidthWzEwMjRd.jpg)