Sylvain Le Bris, Frankreich
Info
Pseudodistoma crucigaster is a colonial sea squirt that occurs in various colors in European waters, mainly in the western Mediterranean.
The sea squirt nestles in small rock crevices and is regularly found on bollards and pillars in port facilities.
Pseudodistoma crucigaster forms flat, mat-like and also domed structures and occurs in various colors such as white, yellow, orange, and gray.
As filter feeders, sea squirts process large amounts of water and can thus absorb toxins such as heavy metals, hydrocarbons, and microplastics and accumulate these foreign substances in their tissue. The long-term effects of the accumulation of toxins or non-degradable microplastics are unknown, but initial scientific experiments have already been launched.Recent studies of these sea squirt colonies have shown that rich and diverse consortia of microbial symbionts are associated with them, but these communities have not yet been studied for most host sea squirts, and little is known about the interactions between host and symbionts.
Dormant colonies showed a reduced gill sac (feeding apparatus) and a thickened cuticle. Electron microscope images also indicated a higher number of microorganisms on the surfaces of the dormant colonies.Accordingly, bacterial sequences associated with environmental sources (sediment and biofilms, >99% similarity) were detected exclusively in dormant colonies. When the sea squirts entered the dormant phase, changes in rare bacteria were observed, including the appearance of strictly anaerobic lines and nitrifying bacterial guilds.
We would like to thank Sylvain Le Bris and Frédéric Andre from France for the great photos of Pseudodistoma crucigaster!
The sea squirt nestles in small rock crevices and is regularly found on bollards and pillars in port facilities.
Pseudodistoma crucigaster forms flat, mat-like and also domed structures and occurs in various colors such as white, yellow, orange, and gray.
As filter feeders, sea squirts process large amounts of water and can thus absorb toxins such as heavy metals, hydrocarbons, and microplastics and accumulate these foreign substances in their tissue. The long-term effects of the accumulation of toxins or non-degradable microplastics are unknown, but initial scientific experiments have already been launched.Recent studies of these sea squirt colonies have shown that rich and diverse consortia of microbial symbionts are associated with them, but these communities have not yet been studied for most host sea squirts, and little is known about the interactions between host and symbionts.
Dormant colonies showed a reduced gill sac (feeding apparatus) and a thickened cuticle. Electron microscope images also indicated a higher number of microorganisms on the surfaces of the dormant colonies.Accordingly, bacterial sequences associated with environmental sources (sediment and biofilms, >99% similarity) were detected exclusively in dormant colonies. When the sea squirts entered the dormant phase, changes in rare bacteria were observed, including the appearance of strictly anaerobic lines and nitrifying bacterial guilds.
We would like to thank Sylvain Le Bris and Frédéric Andre from France for the great photos of Pseudodistoma crucigaster!
