Compare Surirella arctica
Compare
Surirella angusta is similar, but it lacks a craticula-like structure, has higher density of more narrow costae and differs in other details visible under SEM. Small specimens of S. arctica with a poorly developed or eroded craticula-like structure may hardly be differentiated from S. angusta.
Both S. heardensis and S. subantarctica have a craticula-like structure, but it is less robust with narrower costae. These taxa also have more rounded apices, can reach larger size, especially the valve width, and are typically constricted mid-valve. Both taxa have been confirmed only from the sub-Antarctic region.
LM scalebar = 10 µm
Length Range
19–56 µm
19–56 µm
Width Range
6–9 µm
6–9 µm
Striae in 10 µm
22–25
22–25
