Raphes absent. Frustules long and narrow in both valve and girdle view, forming ribbons of cells joined side to side (via small interlocking spines at the valve edges; these not visible with the light microscope). Ribbons often attached to submerged plant surfaces.
Fragilaria, Waiorau tarn, X640 Photo: Otago Regional Council & Manaaki WhenuaFragilaria bloom, Lake Hayes outlet Photo: Otago Regional Council & Manaaki Whenua
Typical habitats
Slow-flowing habitats such as ponds and lake outlets.
![[Fragilaria], Waiorau tarn, X640 Photo: Otago Regional Council & Manaaki Whenua Image](/assets/Tools-And-Resources/Identification/algae/fragilaria640b__ScaleWidthWzEwMjRd.jpg)
![[Fragilaria] bloom, Lake Hayes outlet Photo: Otago Regional Council & Manaaki Whenua Image](/assets/Tools-And-Resources/Identification/algae/fragilaria2__ScaleWidthWzEwMjRd.jpg)