Compare

Tetracyclus glans has a central inflation that lacks notches and the valve apices are pointed.

Tetracyclus cruciformis has a central inflation that lacks notches and the valve apices are capitate to prominently wedge-shaped.

LM scalebar = 10 µm
Tetracyclus emarginatus LM4 Tetracyclus emarginatus LM3 Tetracyclus emarginatus LM6 Tetracyclus emarginatus LM5 Tetracyclus emarginatus LM2 Tetracyclus emarginatus LM1
Length Range
18.8-37.3 µm
Width Range
13.1-19.4 µm
Striae in 10 µm
18-24

Tetracyclus glans

(Ehrenberg) Mills 1935

Iwb 0030 1  Tetracyclus Glans 001 Girdle Band Cropped Small Iwb 0026 1  Tglans 009 Cropped Adjusted Small Iwb 0026 1  Tglans 004 Cropped Adjusted Small Iwb 0026 1  Tglans 005 Cropped Adjusted Small Cas 183038 07282014 051 Adj Cropped Small Cas 183038 07282014 028 Test
Length Range
19.4-37.5 µm
Width Range
13-21 µm
Striae in 10 µm
21-23

Also compare to

Tetracyclus cruciformis

G.W.Andrews 1970

Diatoms of North America is running a fundraising campaign to keep the servers in operation. We need you to reach our $25,000 fundraising goal.

If you use and appreciate DONA, make your DONAtion today.

For the Gift Designation, type "diatom" in the search box and select "Diatom Lab Research Fund". This is the designated fund for diatoms.org.