[Penguin]

Hey, I just added some Nassarius snails to my tank and I noticed that one of them was definitely not a Nassarius. Is it some sort of whelk maybe? Anyone have any info on what it might be? And do you think it's safe with my other snails? I know at least some whelks are predatory. What do you think I should do with it?









Size is about the same as your average Nassarius, but you can see the shape of the shell is slightly different. The body color is different too. It's gray with sort of a mottled appearance. It has a long siphon. When he was in my tank he was cruising all over the LR.

[Ninong]

If you want to turn it over and take a picture of the aperture that would decide it one way or the other.

[Penguin]

I did take one picture of the underside, but the aperture wasn't really visible--just the foot. I'll see if I can get another.

[Penguin]

Ok, these were the best I could do. What do you think?

[Ninong]

I do not think it is a Nassarius. I will go get some pics for you and add them to this post in a couple of minutes.

Be right back.

[Ninong]

Well, this is really frustrating. I tried to get the pics from Dr. Ron's website but his server must be down or something. He's in Montana and it goes down a lot. Almost as bad as Louisiana.

Anyway, when it finally decides to come back up you will find some nice pictures of predatory whelks in this article that match your snail: http://www.animalnetwork.com/fish2/a...wb/default.asp

And in this article you will see a drawing of the aperture of a true Nassarius snail that shows the typical 'grove' that all Nassarius species have: http://www.animalnetwork.com/fish/li...=&RecordNo=166

There are some other pics that I know of online but I may not be able to find them as fast and they are photos of shells. Oh, heck, wait a minute, they're not online, they're in Volume 4 of The Modern Coral Reef Aquarium by Fossa & Nilsen that I was just reading the past couple of days. They, too, show the typical grove in the shell just to the left of the siphonal tube opening. Also, there is a difference in the general appearance of the shape of the aperture and siphonal tube between the Nassarius snails and the other whelks.

If anyone reading this has a copy of TMCRA IV, look on page 90 and you will see pictures of 8 different Indo-Pacific Nassarius species' shells. All have the typical grove to the left of the siphonal tube and all exhibit a small notch at the top of the aperture that I don't remember if Dr. Ron included in his drawing or not. I can't get to his article to double check that but it would seem like maybe that is another characteristic of Nassarius apertures -- not sure if it is unique or not. The other obvious difference is that the predatory whelk siphonal tube is longer and more slendor compared to the Nassarius which appears shorter and more open with a more rounded looking aperture.

Anyway, that's the best I can do from memory without being able to refresh myself with his actual pics right now. Also, IME, my Nassarius vibex have a tendency to stay off the rocks. They are either under the sand, on top of the sand or on the glass. I see them on the rocks only rarely.

[Penguin]

It looks like one of the boring snails then. I don't see a groove next to the aperture, and the siphon is longer and more slender. It also spends most of its time on the rocks and glass. I'm going to have to take it back. Thanks Ninong.