>as i remember largest leech ever found lives on whales! its about 25 cm
>(maybe more).

Charming... remember that next time yo go diving with large whales...

>i cant remember the species, but can say there are several of
>600 spp. live in seas.

That's far more than I'd have expected, but I guess i wasn't
thinking. There's lots of fish out there.

>this doesnt mean that all are ectoparasitic. some are predaceous too!

I would be surprised if most species do not predate when they get the
chance... I believe many freshwater spp eat small worms etc as well
as attacking larger hosts. That is, they are facultative parasites.
In fact external bloodsucking is in a gray zone where predation and
parasitism overlap. As they don't actually LIVE on the host (most
spp, anyway) perhaps they should be regarded as predators.

But I'd suspect those whale-leeches live on their hosts permanently.

I wonder if any attack molluscs?
--
Andrew Grebneff
Dunedin
New Zealand
Fossil preparator
<[log in to unmask]>
Seashell, Macintosh, VW/Toyota van nut

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