Dinoflagellates and bacteria

Charles Krebs · Post by **Charles Krebs** » Thu Feb 01, 2007 12:39 am

My pond sample was not productive so I went outside and took a dropper of water from a rather dirty bird bath in the backyard. Within a few minutes bacteria had settled on the cover slip and beneath them was a very active bunch of (unidentified) dinoflagellates.

The first image shows the focus set on the bacteria on the coverslip. There were two predominant types... one spherical and one spiral-shaped. You can see the very out of focus shapes of the dinoflagellates under them.

In the second image the the focus has been lowered beneath the bacteria and now some of the dinoflagellates are in focus.

Olympus 40/0.95 S Plan Apo, Canon 350D, DIC with electronic flash (both images)

bernhardinho · Post by **bernhardinho** » Thu Feb 01, 2007 5:06 am

Hi Charlie,

very beautiful, due to the very distinct cavitities in the middle section of the Dinos I would go for a Glenodinium species.

Bernhard

Ken Ramos · Post by **Ken Ramos** » Thu Feb 01, 2007 5:36 am

Thought that I might attempt to ID them from Jahns, there are three references. The second on pg: 58 fig. 55 describes part of what I see here but I don't recognize the species you have, having any chloroplasts and the shape is different from from what is shown in the figure but they do have the reddish vesicles. Fig: 56 references the shape but with plates, which I don't see here or maybe I am just not seeing them or any of the other features Jahns references.

Maybe someone else can put a finger on them. Glenodinium spp. best guess.

Charles Krebs · Post by **Charles Krebs** » Thu Feb 01, 2007 10:47 am

My guess would have been a Gymnodinium of some flavor, but I just don't know.
Hey, I knew it was a dinoflagellate

Walter Piorkowski · Post by **Walter Piorkowski** » Thu Feb 01, 2007 11:51 am

Beautiful as always Charles.

Walt

beetleman · Post by **beetleman** » Thu Feb 01, 2007 1:16 pm

Wonderful looking creatures and photos Charles

bernhardinho · Post by **bernhardinho** » Thu Feb 01, 2007 4:01 pm

Charles Krebs wrote:My guess would have been a Gymnodinium of some flavor, but I just don't know.
Hey, I knew it was a dinoflagellate

Well, as Ken pointed out: there are reddish spots (eyespots?) and there aren't any chloroplasts. This excludes Gymnodinium! Dinos with no chloroplasts are very rare. Glenodinium edax is one of that rare exceptions.

Bernhard