Eel & friends

[H2Andy]

I'm sure the ingested Lysmata in my eel tank would be happy to hear that.

hhhmmm..... i don't know that an eel tank is an adequate reproduction of the eel's natural habitat to begin with, so not sure how accurate it is to use an eel's beahaviour
in captivity as a guide for what it would do in the wild...

that said, "nothing eats dedicated cleaners" is probably too wide a statement. but dedicated cleaners are usually extremely safe in the wild, much more so than the part-time cleaners.

 

[archman]

Ha ha Andy, why do you think we had Lysmata in an eel tank in the first place? One of our faculty's a super-ace cleaning behaviorist. Those stupid shrimp are so hard to replace we don't run a lot of tests very often... we've had all sorts of different species over the years however.

Cleaning behaviour on morays is very poorly understood. Shots like alcina's are excellent; unfortunately we don't really know much more than what can be inferred from photography.

 

[H2Andy]

ok... what the heck is a lysmata anyway?

 

[alcina]

arch...you can know that this particular eel did not like it when one of those shrimps stuck a foot in the hole on the side of his head! Too funny to watch him flick his head and the shrimp hold on for dear life (or sometimes get shaken off completely)...

 

[archman]

That "hole" would be the poor eel's spiracle, which is quite sensitive. The shrimps (look like Lysmata amboinensis) cleaning this particular moray are pushing their luck with being too large. Our snowflake would've chomped 'em!

Andy, Lysmata is a genus of hippolytid caridean shrimps containing several cleaner species throughout the world's oceans. These make up some of the largest "shrimp" cleaners, and many aren't obligate. The neat thing about these critters is that you can see evolutionary cleaning specialization between different species. Some types display "better" cleaning behaviour than others, even though they might look similar (and even behave similar when hosts aren't around).

Here's a pretty link I looked up showing a lot of commonly seen hippolytid cleaners. I even learned that there's a coldwater cleaner off of California (L. californica). I LOVE Google!
http://www.malawicichlidhomepage.com/other/lysmata_debelius.htm

 

[alcina]

That "hole" would be the poor eel's spiracle, which is quite sensitive. The shrimps (look like Lysmata amboinensis) cleaning this particular moray are pushing their luck with being too large. Our snowflake would've chomped 'em!

arch - are eels' spiracles like rays' spiracles? And I think sharks have them, too? Can you just clear up what they are for? Thanks!

 

[archman]

In fishes a spiracle is the respiratory egress point. Species which actively pump water across their gills and lack an operculum (i.e. morays, most rays) blow it back out via these holes. Morays are screwy since they lack scales... makes them resemble cartilaginous fishes in this regard.

Insect spiracles are the openings for the snorkel-like tracheae. Maybe the latin derivation refers to breathing... somebody else look it up.

 

[H2Andy]

well, thank you for clearing that up...

and an operculum would be?

 

[alcina]

Morays are screwy since they lack scales... makes them resemble cartilaginous fishes in this regard.
QUOTE]

lost me here...but it could be the kind of day I am having...

I was sure I knew what spiracles were for on sharks and rays, but didn't realise they were the same thing on eels..thanks!

 

[archman]

and an operculum would be?

Oh man you're killing me! Okay, the Operculum ON BONY FISHES is the flexible, bone external covering for the gills. Cartilaginous fishes (sharks and junk) don't have these things... in fact each of their gills is separately compartmented from one another (with bony fishes they're not).

"Operculum" is a biological catch-all as a sort of door or plug. Most snails can stop up their apertures with an operculum made of either protein, calcium carbonate, or in one newly discovered vent snail, METAL.
I'm sure other critters possess what WE term opercula, I just can't recollect them.