Colorado River in Glen Canyon:
Nitzschioid Diatoms Ni-Z

Nitzschia cf. inconspicua Grunow

Nitzschia cf. intermedia Hantzsch

Nitzschia cf. linearis (Agardh.) W.Smith

Nitzschia microcephala Grunow

Nitzschi cf.palea (Kütz.) W.Sm.

Nitzschia cf.paleacea Grunow in Van Heurck

Nitzschia cf. pusilla Grunow

Nitzschia semirobusta Lange-Bert.

Nitzschia sigmoidea (Nitzsch) W.Sm.

Nitzschia sp. 4

Nitzschia cf. valdecostata Lange-Bert. & Simonsen

Tryblionella angustata W.Smith

Tryblionella brunoi (Lange-Bert.) Cantonati and Lange-Bert.

Tryblionella hungarica (Grunow) Frenguelli