Several of us saw lovely, large, s-curved diatoms in our Loch Norse water samples. These belong to the genus Gyrosigma, and are nice examples of pennate diatioms.

The handsome diatom pictured below is one of our own Loch Norse specimens.

The genus Gyrosigma (gyro = round and sigma = curved) belongs to the family Naviculaceae, which includes lots of species that we might see in our local ponds and rivers. Gyrosigma species are often found crawling along the surfaces of mud or sand, so ours may have come off some of the rocks along the bottom of Loch Norse. You can learn more about these diatoms and their relatives, and see more examples of pennate diatoms, at iNaturalists' Naviculaceae page.

Posted on April 2, 2022 02:50 AM by m_whitson