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View Full Version : Please help ID snail/conch ?


markrb1
01/15/2000, 10:05 PM
Looks like it could be a snail or some kind of conch. It hasn't bothered anything in my tank and mostly sticks to the glass. It showed up on some rock and I just decided to keep and, but watch it to make sure it wasn't going to bother anything. This thing has grown very fast and more then doubled in size in 4 months.
Please have a look.

http://www.gis.net/~markrb/what.jpg
http://www.gis.net/~markrb/what1.jpg
http://www.gis.net/~markrb/what2.jpg

Thanks
Mark

rshimek
01/16/2000, 07:18 AM
Well Mark,

It surely IS bothering somebody if it has grown like you say.

The shell morphology indicates a member of the family Muricidae and I would guess it is a small Murex or some near relative.

These are ALL predatory on either 1) small clams or barnacles, 2) other snails, or 3)other animals such as worms, corals, soft corals (diet depends on the species).

Keep it at your tank's risk. They are not reef safe.

Cheers, Ron

reefmanic
01/16/2000, 11:33 AM
Ron,I had picked up some snails awhile ago on my LR and although it didn't look like the above one,it was brown and had similiar shell,It also had a (I might be using the wrong word here?)probiscus,that thing that looks like a snorkle in the front of it and it seemed to use that to track food.I watched this thing attack another snail/slug type thing that only had a half shell and it came in white/black or maroonish,also from LR but what I'm getting at is it safe to assume that when a snail possess one of the probiscus's then it's not an algea grazer and should be considered a predator?I found out the hard way,these things wiped out these snail/slugs b-4 I realized it.The snail/slugs where nocturnal grazers and helped and reproduced alot,I'm hoping that the ones I gave a friend did well and he can give me some back.August

rshimek
01/16/2000, 01:23 PM
Hi Reefm...

Well, the critter you called a snail/slug was probably was Stomatella varia which is a grazer closely related to Astraea and Turbo, and as you indicate they are good grazers.

The presence of a proboscis is not always a good cue to predatory behavior. Queen conchs, Strombus gigas, are absolutely non-predatory and eat only algae, but have a long green proboscis. However, most of the time it is a good cue.

Now, we have to define things a bit better. The structure that looks like "snorkel" in front of the shell is not a proboscis. It is called a siphon and it only serves to direct water into the mantle cavity where the gills are - however, it has the snails equivalent of a nose at the base so it is used in predators to sniff out out food.

A lot of good snails have siphons, Ceriths, Nassarius, etc. So it can't be used as a character with any reliability.

Snail proboscides always are kept internally until the animal starts to feed and then are extended out of the mouth and used to attack the prey. Nassarius and Strombus will have proboscides, and are harmless to other tank inhabitants, but they are about the only ones.

Check out this article for more information about how to recognize good from bad in predatory snails.
http://www.animalnetwork.com/fish/aqfm/1998/oct/wb/default.asp

Cheers, Ron


[This message has been edited by rshimek (edited 01-16-2000).]