Copepod under attack

hkv · Post by **hkv** » Wed May 10, 2017 2:17 pm

In a water sample from Åland I saw one copepod that deviated from the rest. It was slow and looked heavy in the water, but was still swimming around. At close inspection it looks "hairy", so I decided to zoom in with the compound.

It turned out to be literally covered in algae. I have learned from other forum's members that it is not unusual with growth of epibiotic microorganisms, such as algae, on copepods and other marine crustaceans. However, this lady with eggs was obviously struggling to swim with all these algae growing on her body. I have seen limited algae on crustacenas and mollusks before, but not as severe as this.

An interesting side note: I had the copepod in 5% Formaldehyd for a few minutes to immobilise her. It turned out that the treatment totally turned off the autofluorescence capability of the algae. I imagined this copepod would be fantastic under UW light with all the algae, but there were absolutely no emission of light when excited with 400 nm.

Here are the images:

4X objective, crossed polarizers with retarder:

10X objective, polarized light with retarder:

10X objective, polarized light:

10X objective, polarised light:

zzffnn · Post by **zzffnn** » Wed May 10, 2017 5:09 pm

Very nice images and interesting story as well. Thank you for sharing!

carlos.uruguay · Post by **carlos.uruguay** » Thu May 11, 2017 5:30 am

Nice!!
Very interesting!!!!
We know very little about everything

Jacek · Post by **Jacek** » Fri May 12, 2017 12:26 pm

WalterD · Post by **WalterD** » Fri May 12, 2017 11:32 pm

These are absolutely great images! First time I've seen this too.

I would (I mean this in a positive way) try to reduce the white clipping in the centre of the image 1 and 3, it may be a bit dominant in these fantastic photo's. Anyhow that's also my personal taste.

Thanks for sharing.

hkv · Post by **hkv** » Sun May 14, 2017 3:25 pm

WalterD wrote:These are absolutely great images! First time I've seen this too.

I would (I mean this in a positive way) try to reduce the white clipping in the centre of the image 1 and 3, it may be a bit dominant in these fantastic photo's. Anyhow that's also my personal taste.

Thanks for sharing.

Thanks! Yes, you are right. I will remake these and reduce the white spots. Now when you have mentioned it, it is the only thing I see when I look at the images!

Marek Mis · Post by **Marek Mis** » Wed May 17, 2017 4:35 am

Beautiful, very colourful images !

Marek