Compare

Surirella terryi has wider porcae and a more thickly silicified axial area. Surirella minuta is smaller, less heteropolar and lacks porcae. Surirella splendida is larger, with a more acute headpole and wider porcae.

LM scalebar = 10 µm
Surirella tenera LM1 Surirella tenera LM3 Surirella tenera LM5 Surirella tenera LM6 Surirella tenera LM8 Surirella tenera LM9 Surirella tenera LM11
Length Range
75-134.5 µm
Width Range
24.0-31.5 µm

Surirella terryi

Ward ex Terry 1907

Surirella terryi LM1 Gc 42664 Fossil Phila  Sur Ter1A Copy Acadia Np 057A  Gr Mead  Sur Ter2A Boyer  G7 9  Lees Pond Bristol Ct  Sur Ter27B Cas 600484 2  Lk Ozette Wa  Sur Ter6 Copy Gc 115390B  Sycamore Lnj  Sur Ter24A Copy Gc 114834A  Kent Co De  Sur Ter1A Publ Copy
Length Range
67–176 µm
Width Range
23–35 µm
Striae in 10 µm
21–26

Surirella pinnata

W.Smith 1853

Surirella minuta LM1 Surirella minuta LM5 Surirella minuta LM2 Surirella minuta LM3 Surirella minuta LM6 Surirella minuta LM4 Surirella minuta LM7
Length Range
18-71 µm
Width Range
8.5-14 µm
Striae in 10 µm
25-32

Also compare to

Surirella splendida

(Ehrenb.) Kütz. 1844