Dec 29, 2007

A Place of Their Own

You're looking at the puckered face(s) of the lamprey, or lamprey eel. These jawless parasites aren't actually truly representative of lampreys in general--most lampreys aren't parasitic. In fact, these nasties (I've gone fishing for them before, so I know!) aren't truly representative of fish in general, due to differences in morphology and physiology.

These differences include: no scales, no paired fins, and a single nostril on the top of the head. And since they are cartilaginous (no bone skeleton), they strictly aren't even vertebrates.

These fish (or whatever they are) have no true taxonomic home. That's why, I believe, they have turned to latching themselves onto whatever host they can find, if for no other reason than to find a place to belong. Much like an obnoxious younger sibling.

8 comments:

brian said...

That evil parasite mouth just sends shivers through me every time. >_<

Arachnophile said...

LOL is anyone else reminded about their He-Man toys... Yes, I was a girl who played with He-Man. *sigh*

These guys have always fascinated me too. I mean, as you said, they are taxonomically so weird and are just instantly horrible to look at. Very cool.

Jason said...

The top pic makes them look cute!

Erin said...

I like lampreys even though I'm torn between finding them sort of cute and hideously ugly. I did not know they had only one nostril, however--thanks for broadening my knowledge of these plunger-shaped creatures!

Kritter said...

Picking on your brother again?

Dave Godfrey said...

Vertebrates are usually defined as the last common ancestor of lampreys and gnathostomes (jawed vertebrates) and all its descendants.

As always there is some debate. DNA analysis indicates that hagfish and lampreys are more closely related to each other than either is to the rest of the chordates, whereas all the morphological information points to hagfish being much more primitive.

Meirav Rath said...

What do you mean, no taxonomic home?! They're Cyclostomata!

Shay said...

an obnoxious younger sibling with rows of needle sharp teeth and one nostril.