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Epilithic Diatom

Genus: Fragilaria


Attached to submerged rock along shoreline of man-made lake in SW Pennsylvania. pH level of water was 7.3


Diatoms are single celled golden algae that are encased in glass-like shells (frustules) composed mostly of silica that are intricately marked and nearly indestructible. Epilithic diatoms are diatoms that are not defined by their physical characteristics but by their habitat. They attach themselves to rocks that are submerged in both slow and fast moving waters.

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William_Dembowski 4 years ago

Unfortunately, much of the additional info will be the same for most of the Epilithic Diatoms. Identifying them to the genus level isn't so bad; but taking it down to the species level is virtually impossible for the amateur; we just don't have necessary equipment. The genus Navicula, for example (not this critter), has over 1,200 species; many of which require analyzing their genomes in order to assign a species.

But I will contribute the best info that I can.

DanielePralong 4 years ago

Thank you for the extra info William!

William_Dembowski 4 years ago

As bayucca suggested, I am going to try to include more info with my micro-spottings.

Ava T-B
Ava T-B 4 years ago

Thanks for the information as well as the photo.

Spotted by

Pennsylvania, USA

Spotted on Apr 4, 2016
Submitted on Dec 13, 2016

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