Help ID, round salt water diatom, likely Coscinodiscus

Images made through a microscope. All subject types.

Moderators: Chris S., Pau, Beatsy, rjlittlefield, ChrisR

carlos.uruguay
Posts: 5358
Joined: Thu Feb 23, 2012 8:05 pm
Location: Uruguay - Montevideo - America del Sur
Contact:

Help ID, round salt water diatom, likely Coscinodiscus

Post by carlos.uruguay »

In the video we see a circular diatom of salt water.
We first see an living exemplary. Then we see its empty 'home' (frustule).
The frustula has a fine carved that refracts light in dark field.
We assume that belongs to the genus Coscinodiscus.
Measures about 120um in diameter and was found on the shores of the Atlantic ocean - La Paloma - Uruguay - South America.
We appreciate any help in their identification
Oblique light and dark field
Link:
http://www.youtube.com/watch?v=vnQqhRyexfY
Regards
carlos

René
Posts: 467
Joined: Sun Oct 08, 2006 4:22 am

Post by René »

Hi Carlos, looks like C concinnus to me.

Best wishes, René

carlos.uruguay
Posts: 5358
Joined: Thu Feb 23, 2012 8:05 pm
Location: Uruguay - Montevideo - America del Sur
Contact:

Post by carlos.uruguay »

Thank you very much René!
I am surprised by the extremely thin weft of the frustule

René
Posts: 467
Joined: Sun Oct 08, 2006 4:22 am

Post by René »

Yes, C. concinnus is very finely structured. Nevertheless, I just saw it is quite small for C. concinnus, and the center could fit, but is atypical. In retrospect, Hyalodiscus might fit better. But I haven´t come across them much, and certainly not alive, so I wouldn´t know whether the chloroplast shape fits with your spec. For sure Podosira (very much related to Hyalodiascus) has way different chloroplasts. So, please don't take my word for it.

Best wishes, René

carlos.uruguay
Posts: 5358
Joined: Thu Feb 23, 2012 8:05 pm
Location: Uruguay - Montevideo - America del Sur
Contact:

Post by carlos.uruguay »

Thank you again René
The weft is very similar to that of these beautiful photos yours:
http://www.photomacrography.net/forum/v ... d946e98d1f
carlos

Post Reply Previous topicNext topic