Centipede-like kelp denizen

[Frank O]

Hi all, last night we did a couple of dives off Palos Verdes, California. The kelp was quite heavy, which made getting back to the boat challenging. In fact after we were all onboard, there were a fair amount of kelp pieces scattered around the deck.

When I was cleaning up the boat, I noticed what at first appeared to be a piece of kelp but which later proved to be an invertebrate of some kind. It was about 1-1/2 inches long and generally centipede-like -- segmented, many feet, and two antennas at the "head" end. It was exacty the color of kelp -- greeny-brown -- and translucent. There was a very prominent dark cord or canal running down the core of the body. No photos, I'm afraid. Does this suggest a particular creature?

 

[Fish_Whisperer]

Some kind of fireworm?

 

[Mr.X]

It's a type of a marine isopod. I'll have to track it down. They are greenish, longish and have a dark line running down the dorsal surface ...just like you mentioned.


Scroll to the bottom. Did it resemble the green isopod?

Feeding at Eagle Cove

Cheers,

X

 

[SteveAD]

some species of bloodworm or bristleworm

 

[Frank O]

It's a type of a marine isopod. I'll have to track it down. They are greenish, longish and have a dark line running down the dorsal surface ...just like you mentioned.

Scroll to the bottom. Did it resemble the green isopod?

Feeding at Eagle Cove

That's close! It resembles even more this picture of the isopod Idotea:

http://www.pac.dfo-mpo.gc.ca/sci/OSAP/projects/plankton/zooplankton/images/isopoda/idotea.jpg

I'm happy to think of it as "Idotea or similar," unless anyone has other information on what kelp-hugging isopod might be typical to Southern California. Thanks for the help.

 

[Mr.X]

That's close! It resembles even more this picture of the isopod Idotea:

http://www.pac.dfo-mpo.gc.ca/sci/OSAP/projects/plankton/zooplankton/images/isopoda/idotea.jpg

I'm happy to think of it as "Idotea or similar," unless anyone has other information on what kelp-hugging isopod might be typical to Southern California. Thanks for the help.

This is fun. It reminds me of one summer where I spent two weeks digging up sand at the beach and classifying amphipods by zones.

Here's a picture of one that shows the band. I also caught one way up North 61?.

http://www.wallawalla.edu/academics...lvifera/Family-Idoteidae/Idotea_resecata.html

X

 

[Frank O]

This is fun. It reminds me of one summer where I spent two weeks digging up sand at the beach and classifying amphipods by zones.

Here's a picture of one that shows the band. I also caught one way up North 61?.

Idotea (Pentidotea) resecata

Yes, I'd seen pictures of Idotea resecata and thought that was it. I'd say case closed. Thanks again for the help!

 

[drbill]

Yep they are fairly common on kelp when you really look. We used to get them by the hundreds when we gathered drifting kelp rafts to study what was being transported. There are other species too which, if I remember correctly, have different uropods.