Snail ID? Good guys or Bad guys?

[FishPharmD]

Does anyone have any experience with these snails?




I hope these showed up. If not, they're supposedly called Nassairius snails, very small, black, conical shells. Breeder claims they eat red slime algae and are reef-safe. Am I making a mistake by using these guys to clean out some algae? I'm gonna get some other "critters" later, but I won these for practially nothing on eBay. Do they go in the aquarium, or in the trash?

Thanks!

[scubadude]

Maybe even more, but there are 2 different ones that I have seen that are talked about alot

Nassarius Obsoleta
Nassarius Vibex

Here is a quote from Dr. Ron Shimek

The name Illyanassa obsoleta, although related to true Nassarius, they belong to a different group.

These animals are more omnivorous and predatory than are true Nassarius and will, as you have seen, graze on algae. True Nassarius will eat only carrion and meaty based foods. True Nassarius will not prey on living animals. As you have seen, Illynassa will.

Illynassa are temperate animals that will survive for some period at reef temperatures but which really don't do well at those temperatures for extended periods. Their lifespan is shortened over what it would be at their normal temperatures.

Both of these species will depost egg capsules which will hatch to release planktonic larvae. These larvae need to be fed, and in most cases in aquaria they are, instead, food for something else. I think the odds of any of them surviving through the larval period in a home aquarium are slim to none.
.

So with that being said Dr. Ron is saying that the Vibex are the better snails, and I have noticed that they are a bit cheaper, I do believe the snails you are referring to for sale are the obsoleta, judging from what I have studied on their origins and noting they are coming from someone more than likely collecting them in NC according to the ebay origin of the seller. I will say that the obsoleta I believe is getting a bit of a bad wrap from Dr. Ron as there are numerous hobbyist that have supposedly tried these snails with no ill effects. I believe they have preferences to the types of food they eat and will eat what they like the best first and they both appear to be bottom grazers eating detritus, and the obsoleta appear to eat algae more apparently then the vibex. I believe both of them will eat decaying food or leftover food supposedly the vibex will not eat live food. I personally have used the Vibex and they will not live long unless you feed them I would love to try some of these obsoleta and I think that is a fair price for them.....I say go for it Just keep an eye on em.

[Ninong]

I love the seller's attitude. To the best of his knowledge he is the only online seller of those snails qualified to give you a truthful answer about anything reef-related and he can't even spell Nassarius.

There is another vendor on eBay who has been selling these snails for a couple of years now. We got into a "discussion" with him on Reef Central, where he is a registered member. He insisted on calling them Nassarius obsoleta even though his reference for that classification was several decades old and no longer valid. He finally changed his ad copy to "Nassarius I.O. snails." The trick there is that he is using the Family name followed by the initials for the correct scientific name, which consists of the genus and species. Ilyanassa obsoleta happens to belong to the Family Nassariidae, the same as Nassarius spp. snails but it is incorrect to call it by the Family name.

The snails pictured appear to be the Eastern Mud Snail, Ilyanassa obsoleta. You can pick them up virtually anywhere along the East Coast of the U.S., which is why you will notice that most of the eBay sellers have coastal addresses. You can also pick them up around San Francisco Bay, although they are not native to the West Coast and are considered an unwelcome intruder there: http://www.elkhornslough.org/researc.../aquatic11.htm

Many, many aquarists have purchased these snails from the many online vendors that have popped up over the past couple of years on eBay. They are a temperate species. Reef tank temperatures are higher than their typical range. They will not survive as long at reef tank temperatures as they would in a tank kept at cooler temperatures. By the way, they can survive freezing temperatures in their natural range by migrating to deeper water from the mud flats.

As pointed out by Scubadude (and Dr. Shimek), they are omnivorous and will eat algae. The Nassarius spp. snails recommended as good sand bed stirrers in reef tanks are scavengers on carrion and meaty detritus. Some hobbyists have reported problems with these Ilyanassa obsoleta snails in their reef tanks and others seem satisfied and report no problems.

As far as the idea that if they are cheap enough then it's a good deal, then how about some nice cheap "anemone rock?" I know an LFS that sells some nice "anemone rock" at a very good price. The only problem is that the anemones in question are Aiptasia. :eek3:

[Poseidon]

Don't feel bad, FishPharmD. I bought some of these last October. Didn't post a question here first, just thought they were a good deal. Both Rocky and Ninong are right about the tempature issue. Out of the 25 I bought I have maybe 2-3 left. So they lasted 4-5 months at 78-82 tempatures. I have Astrea snails that have been with me 2-3 YEARS, so it turns out not to be the greatest deal, but they didn't seem to hurt anything in my tank either.

[Ninong]

Don't feel bad, FishPharmD. I bought some of these last October. Didn't post a question here first, just thought they were a good deal. Both Rocky and Ninong are right about the tempature issue. Out of the 25 I bought I have maybe 2-3 left. So they lasted 4-5 months at 78-82 tempatures. I have Astrea snails that have been with me 2-3 YEARS, so it turns out not to be the greatest deal, but they didn't seem to hurt anything in my tank either.

Mike,

Your experience is typical of what I have read from people who purchased these who were regular board members, if you know what I mean.

Here is someone who just registered today on Reef Central so that he could post a favorable review of the Ilyanassa obsoleta snails he purchased on eBay. http://reefcentral.com/forums/showth...14#post2315314

According to this new member his I. obsoleta snails are not only thriving, they are actually reproducing in his system. Not only does he see lots of eggs, as we would expect, but he also claims that he has new little snails. Wow! That's certainly unexpected. Just goes to show you that not everyone's experience is the same.

I thought I would check that guy's profile to see what part of the country he lives in -- maybe it's something in the air there -- but unfortunately he forgot to give any identifying information in his profile. None at all. Pity. ;;

[anthworks]

These snails are predatory. I had a clam several years ago that was doing great then one day the clam was gapping very badly so I picked it up and heard something rattling around inside the clam. When I inspected the snails had entered into the bottom of the clam and eaten it from the inside. All that was left was the mantle.

Be warned.

[scubadude]

These snails are predatory. I had a clam several years ago that was doing great then one day the clam was gapping very badly so I picked it up and heard something rattling around inside the clam. When I inspected the snails had entered into the bottom of the clam and eaten it from the inside. All that was left was the mantle.

Be warned.

Hey Anth

Yeah but the question is are you sure the snails killed the clam? If so how are you sure? if the snails sensed demise of the clam they will eat the clam which is better than letting it decay in your tank. Clams are very sensitive IMO and its hard to pinpoint cause of death with them.

[Ninong]

Hey Anth

Yeah but the question is are you sure the snails killed the clam? If so how are you sure? if the snails sensed demise of the clam they will eat the clam which is better than letting it decay in your tank. Clams are very sensitive IMO and its hard to pinpoint cause of death with them.

Scubadude,

According to what you yourself just posted from Dr. Ron it's possible:

"These animals are more omnivorous and predatory than are true Nassarius and will, as you have seen, graze on algae. True Nassarius will eat only carrion and meaty based foods. True Nassarius will not prey on living animals. As you have seen, Illynassa (sic) will."

[anthworks]

Hey Anth

Yeah but the question is are you sure the snails killed the clam? If so how are you sure? if the snails sensed demise of the clam they will eat the clam which is better than letting it decay in your tank. Clams are very sensitive IMO and its hard to pinpoint cause of death with them.

Later after investigation I noticed several small holes drilled into the bottom of the clam shell for entry. From that point the snails must have entered and multiplied. No other corals were affected by the snails.



But I do find is strange that the clam had no defense from invasive attacks like these. Maybe it was sick and was not able to defend its shell which I assume it does by secreting more shell over the point of entry.. like a pearl and a grain of sand in the oyster? This was noted by Delbeek and Sprung in one of there books.

[Ninong]

Later after investigation I noticed several small holes drilled into the bottom of the clam shell for entry. From that point the snails must have entered and multiplied. No other corals were affected by the snails.

Then they weren't Ilyanassa obsoleta because snails of the Family Nassariidae do not have direct development, they emerge from the egg capsules after a period of embryonic development as planktotrophic veliger larvae and they do not feed that way. There are several snails, some of the Murex snails come to mind, that are capable of boring holes in the clam using acid secretions that dissolve calcium but not any of the dog whelks (Family Nassariidae).

[scubadude]

First I had to look up Omnivorous in the dictionary for reference

om·niv·o·rous ( P ) Pronunciation Key (m-nvr-s)
adj.
Eating both animal and vegetable foods.
Taking in everything available, as with the mind: an omnivorous reader.

Ok heres the part that confuses me, Just because it eats animals doesnt mean its a predator right!? Just like Dr. Ron pointed out on the Vibex they could eat meat that is dying or ill healthed animals, If memory serves me correctly that is one of the features of nassarius they can detect animals dying or decaying so if an animal is on its way (died from something else) then its very possible that these snails could be taking the rap from some other predators. So if this is the case wouldnt this snail be beneficial to our systems if by chance something does happen to die they are there to mop up the mess.

Ninong,
I havent seen nassarius (vibex or obsoleta) actually kill anything so Im not going there And its funny that alot of ppl that I talked to say they (obsoleta) are GREAT and that yes they will eat meat (maybe even prefer it) but will not actually harm any animals. Joy @ Harbor Aquatics sells these snails for quite some time now and has had no problems with them supposedly and neither have her customers. I also want to point out that ppl can easily mis-identify these snails in comparison with whelks which are definately predatory. I never agreed to Dr. Rons study on the obsoletta...never disagreed to it either, I am saying though that the obsoletta seem to be getting a bad wrap from Dr. Ron according to alot of hobbyist.

anthworks,
You know about pyramidillae snails? They actually bore through clam shells as well and are pretty small....Just trying to point out some other possibilities here ....seems like we dont have enough conclusive evidence to blame the Obsoletta but since its the most likely candidate some are labeling it as a predator snail.

Poor FishPharm....he just asked a question

[zhenya]

You know about pyramidillae snails? They actually bore through clam shells as well and are pretty small....

Rocky,

I didn't know this snails could drill holes in the shells of clams or other snails and thought that they mostly fed on lymphatic fluids of the host.At least as it is described by Daniel Knop.
I also were under the impression that only gastropods from the family of Muricidae could drill holes as Ninong had indicated.I think it is one of the distinctive characteristics of this type whelks and separates them from whelks like,let say Buccinids,for example.

[scubadude]

Rocky,

I didn't know this snails could drill holes in the shells of clams or other snails and thought that they mostly fed on lymphatic fluids of the host.At least as it is described by Daniel Knop.

Touche! You are right Gene
I totally goofed on that statement

I also were under the impression that only gastropods from the family of Muricidae could drill holes as Ninong had indicated.

Actually there are sponges and algaes that bore holes through the clams too, check out pg 111-113. I have had the pyramidillae snails and they seemed to breed in little tufts of algae that where on my large deresa. I still have the shell and where the algae was present there are small holes here is a picture of the algae and pyramidillae snails

[Ninong]

Rocky,

Nassarius spp. snails are dog whelks and they are not predatory like other whelks. Ilyanassa obsoleta snails are omnivores, unlike true Nassarius spp. snails. They are in a completely different genus. Humans, chimps, gorillas and orangutans are all members of the Family Hominidae but there are considerable differences between them.

The reason Ilyanassa obsoleta's natural range stops at northeastern Florida is because it cannot survive in warmer waters further south. It has invaded the west coast from Vancouver all the way down to Monterey, California but no further south because the water temps are too warm.

Interesting additional information for you:

The mud snail, Ilyanassa obsoleta (formerly Nassarius obsoletus) is a common intertidal mollusc found on both coasts of North America from Labrador to northeast Florida and Vancouver to central California. It inhabits silty or muddy sand, low energy beaches where it may occur in large aggregations (Fig 12-48A). It is ideal for the laboratory study of anatomy and behavior of prosobranch gastropods

Ilyanassa is often found in dense herds of uniformly aged individuals (Fig 12-48A). The snails respond positively to the scent of conspecifics by following their mucus trail and this results in aggregation. These snails can be very common on muddy sand low-energy beaches in salt marshes and along tidal creeks.

Ilyanassa is the intermediate host of a blood fluke (Austrobilharzia variglandis, Platyhelminthes: Trematoda) whose definitive host is a seagull. The fluke cercaria (Fig 10-35) are released from the snails into shallow water where they may inappropriately penetrate the skin of wading or swimming humans. They are unsuccessful in this attempt and cannot enter the blood and do not complete the life cycle in humans. Before dying, however, they cause a dermatitis known as swimmer's itch. (The cercaria of other flukes can also be responsible for swimmer's itch in both fresh and salt water.) http://www.lander.edu/RSfox/310ilyanassaLab.html

The point I would like to make is that there are very good reasons why Ilyanassa obsoleta is not as appropriate for reef tanks as true Nassarius spp. snails besides the simple fact that they will not survive more than a few months at temperatures in the high 70's to low 80's. I don't think anyone selling them for reef tanks is providing a good service. Premium Aquatics shipped some out a couple of years ago because their supplier shipped them in error but when the error was brought to Jason's attention he contacted all those customers and informed them and replaced the I. obsoleta with N. vibex. Maybe you should explain to Joy that they are not a good idea for reef tanks. She should stick to Nassarius spp. snails instead.

[FishPharmD]

Ok, well, this turned into an interesting thread! So should I leave this guy some bad feedback for stating that this snail is a good reef snail? Should I even put them in my tank? Or should I just count my chips and chunck them in the trash can? Thanks.

[Ninong]

Ok, well, this turned into an interesting thread! So should I leave this guy some bad feedback for stating that this snail is a good reef snail? Should I even put them in my tank? Or should I just count my chips and chunck them in the trash can? Thanks.

You now have the information. The decisions are all yours.

[baconbits]

I just wanted to put my two cents in here. Two weeks ago I purchesed 50 of these snails off the internet. (Illysana sp.) I had no problem getting them or acclimating them. It did strike me a little odd how they could survive in the box, not heat, when the average temp where I live is about 30 degrees F this time of year. Anyway, they have not touched a bit of algae in my tank and I contiune to have to scrape the glass. They have however begun to die and that is leading to a lot af decaying snail flesh(albeit it also is giving my blue-lgs a feast) Anyway, I would steer away from these and stick wih a more proven species. IMO

[thesnailman]

The reason your snails were dying was the hemits are preditors and were killing them and taking their shells and the notion that water temps in the 70 to 80 range was killing them is simply not true. i have kept these snails for ten years and i can tell you their one of the best on the market!

[saltjunkie]

i bought 100 of them with the expectations tht they would die.. i have never had any snails live a long time anyhow.. put some in my sump and my main tank..

i have a few crabs... less than 10... but it took my snails a few months to really all the way die off..
i wouldnt buy them again. but they did the job i needed,at the time, stir my sand bed..
i think the RISK outweighs the potential benefit!

[thesnailman]

Please explain the risks? how often do you do water changes and what percentage do you do?

i think the RISK outweighs the potential benefit!