a Copepod (2 photos added)

[Franz Neidl]

A marine Copepod - relatively big with 610 µm.
Maybe somebody knows the species or the genus?

Obj. 10x DIC, stack with 5 pictures.

Franz

[Charles Krebs]

Another unusual subject, and once again very nicely photographed!

[BJ]

hi Franz,

just a very quick comment. I think it is a "copepodid" stage of a copepod which parasitises fish skin. These are often known as fish lice. There are very many species of these parasitic copepods and I suspect it would be very difficult to identify the species.

In a typical parasitic copepod (search for Caligus, the largest genus), there are two planktonic nauplius stages followed by the copepodid stage (followed in turn by a number of attached stages). The copepodid is the stage that finds the host fish and first attaches to the fish. The body of the copepodid is simplified from the nauplius with most appendages reduced BUT a pair of appendages are modified to "claws" to grab on to the fish. Your beautifully detailed photo shows a pair of "claws" very clearly...hence my tentative ID.

must rush....

but thanks for all the great photos...really love the tintinnid and Chaetoceros

regards
brian

[Franz Neidl]

Charles: thank you for your answer!

Brian: I did'nt expect a parasitic copepod, but your explanation make it much easier to understand the anatomy of this strange animal - specialy the unusual position of the eyes (in the middle of the animal!) and the claws.
I add two pictures.

Franz