Part 4: Anatomy (What IS That?!)

Part 4: Anatomy (What IS that?!)

           All right. Now it is time to discuss a little about shells, mating behaviors/appendages, and various body parts of the snail. Since a picture is worth a thousand words, here are some pictures and a few words.

I realize some of these are obvious, but still. 

That vent is also the entry point on females for mating. The reproductive organs are located inside the whorls through a tube that goes down the vent.

Something really cool about these guys is that they have the ability to change the shape and length of both their snorkel and their vent. They can retract, flatten, and or open their snorkel so it looks just like their vent. They can also close and form their vent into a little tube that looks exactly like the snorkel when it is pulled in. They can't lengthen their vent like their snorkel though. It stays just under their shell no matter what shape it is.

                 Ok I realize that most of these terms aren't scientifically correct, but I don't care. Snorkel is what I call it and it is also easily understandable.

             Okay, so now we come to the mouth.  These guys have a harder outer layer that you can see in the above picture. The white outlines just inside the mouth. Then in between those are two sets of bristles lined up vertically that point down and towards the center of the mouth. They spread these bristles bringing them up and apart, then scrape down and inwards. And that is how they eat! I drew a goofy picture below to help illustrate that. Have a laugh and learn something new. lol

Here are also several websites that have awesome up close high definition shots of a snails mouth in action.
This first one is in spanish so you will have to use your browser to tranlate, but it shouldn't be much of a problem since this site only really has pictures and little info.

This is a flicker photo of a snails mouth:

This is the care section of the apple website. It has a portion that describes in detail a snails mouth and has a great picture too.

This next website is in German so you will have to translate with your browser and it doesn't focus on just Pomacea diffusa, but many different species of snail. It has a lot of great info, although much of it I haven't been able to corroborate on any other sites. I like this website for the awesome pictures and videos. Click on the link that says "peak apple snail (Pomacea diffusa)" to get more info. This is another name for the mystery snail. Just above that section has a video and a couple of great pictures of a snails mouth as it feeds.

              Now I am sure many of you are wondering by now, "How do you tell the difference between a boy and a girl snail?" Well when it comes to mystery snails, they are either a boy or a girl, not both. Unlike many snail species you need one of each sex for mystery snails to reproduce. Although there have been rare reports that in a single sex environment a male has changed into a female. Again this is very rare and not commonly seen. Sexing these snails is actually a very simple and easy process. Although it can just be really tedious at times. You need a lot of patience. Basically you wait for the snail to poke it's head out of its shell so you can get a look at the space inside, right behind the head. If there is a white penis sheath then you have a male. If there is just an empty space with nothing but mantle, then you have a female. Here are a couple of pictures to illustrate, and no I didn't draw these ones. I wouldn't torture you with more of those!

For the males the sheath is always on the right, (that is the snails right, your left when holding the snail facing you),  so if you aren't careful and get a look on the left side behind their head you may end up mistaking the gender for a female. 

This is a picture of Ingot. When his shell lifted up, it gave a clear view of the sheath underneath.

This is Apollo crawling around on Escargo, and you can see his sheath just behind his head under his shell.

           Oh I forgot to mention earlier that the snorkel is always located on the snails left, the vent is always on the right, and for a male the penis sheath is always on the right and that is also the side they mount the female on. This can be very strange looking if you have never seen it before. The male snail's penis will look very much like some sort of long parasitic worm when it is fully extended out of the shell. Don't panic your snail does not have a big nasty worm invading it's shell. You probably won't see it though. Very rarely can you see much even when snails are mating.

You can see the sheath located inside the shell to the right of the snail's head. The sheath is always on  the right and this is always where the member extends. The same side as the vent. Opposite the snorkel. Don't get those two parts confused. Both male and female snails have snorkels on their left hand side.

Meet Big Bertha! This is one of Bully's and Escargo's daughters. If this were a male then there would be a white sheath on our left hand side (snails right) in that space behind the head. I am sorry I drew the arrow pointing on the wrong side. Just make sure you look on the correct side if you do this yourself.

            Here is a great link that has more pictures to help you distinguish male from female in the snail world.

            Okay so now you know how to tell the difference between male and female snails.  Moving on to the next section. Mystery Snail reproduction behavior.
            Often what happens is people buy a couple of mystery snails then panic when they see what they think is the snails "fighting", or attacking one another. This in fact is simply a male snail mounting another. The male snail climbs on top of another snail (not always a female) and moves its head directly to the right side of the other snail's vent. This is where the long whitish appendage is inserted to transfer sperm.

Bully and Escargo
Apollo mating with Escargo.

               Females often simply ignore their suitors. They continue cruising or eating or napping. On occasion though they will twist violently, trying to rid themselves of their admirer. I have even seen one of my females twist and turn, knocking her suitor against the glass. The guys don't give up though and stubbornly hang on until the female resigns herself to his affections.

Bully and Apollo.
Here we have a male mounting another male. This is common and allows one to properly identify the gender of the top snail.  Don't assume the one on the bottom is female though, as you can see snails don't really care about gender when it comes to breeding.

Apollo, Bully, and Escargo.
Now this was interesting. I came across this and immediately felt sorry for  the lady. She really looked like she needed a break. I don't know if she was releasing some sort of hormone or what, but for about 10 days or so this poor lady wasn't given a break. When one male came off it either took a quick pump of air and then reattached or another male took its place.

          Referring to the last picture I have noticed a period for each of the females where the males absolutely won't leave them alone. Not even to eat. It usually lasts over a week. During which and even after the female furiously lays egg batches. As many as 5 in one week. Then usually follows a dry spell where she will go as long as 3 weeks without another egg batch, although the males still occasionally mate with her, with much less fervor.
               A word of caution. Remember when earlier I said people panic and assume two snails are fighting when they are actually mating? Well males and even females do perform a certain behavior that can result in serious injury or even death. Specifically it is when they violently twist, like I described the females doing to remove the males. I have witnessed males "fighting" for females. Really they are just trying to muscle in and push the other male away. Apollo here has even pushed an already attached male away from a female and took its place.
           One day all three of my males were chasing Escargo. One would get up on her back and one of the others would try to push in and they would both violently twist and knock their shells against each other. At the time I thought it really funny. As it turned out it was deadly for one of my males. Ingot, the smaller gold male ended up separating his mantle from his shell. Basically the snail is no longer attached to the inside of its shell. This is always fatal and there isn't anything that can be done. After their battle Ingot simply curled up and didn't move until he died a days later. (I knew he was still alive because I reached in and picked him up and he would move and twitch in response, but wouldn't come out of his shell.)

Here is the video of them "fighting" over Escargo. You can see Escargo twist violently several times, trying to rid herself of her suitors. Also observe how violently Ingot and Bully twist themselves in an attempt to wrest Escargo from the other's grip.

              Snails cannot bite, crush, scratch, or even crack each others shells, but they can harm themselves with this violent twisting motion. For the most part leave your snails alone, even when a mating confrontation gets a little heated, but if you see them start to twist themselves about, I suggest giving them a gentle poke with your finger to get them to revert back in their shells and give it a rest.

Next Page: Part 5: Safety!


  1. how to you get rid of cracks on the shell like the ones on bully?

  2. As far as I know there is no way to correct those unsightly white ridges and cracks along a snails shell. This is permanent damage due to bad water quality, lack of food or low quality food, or rapid change in temperature, or rough handling, (being smacked around or scraped against a rock), that the snail experienced in the past. Some just seem to develop that way. Its the same thing with tortoises, once their shell is damaged or deformed, especially due to diet, it stays that way, no matter how healthy or perfect conditions you provide in the future. Bully had high quality conditions and food from the moment I bought him, but even when I bought him the signs and many of these "cracks" were already there. Where ever he came from he went through some tough times that just permanently marked him. There may also be a possibly for genetic tendencies for this type of "bad shell". I don't believe that was a case with Bully though, as he sired many offspring and they all had perfectly healthy offspring. In this case there isn't much you can do except give them high quality food and perfect water conditions and hope it helps. It never did with Bully, his shell just degraded as he aged, which in part is normal, just not to such an extent as Bully. Sorry I couldn't be of more help this time.Thanks for visiting!

  3. I have been searching for information about mystery snails and couldn't find ANYTHING. Thanks so much for this site! I am still reading through, but was you have any idea how long after mating do they lay the eggs? Two of mine have been mating for what seems like two days now. I'm just wondering when I should be expecting eggs.

    1. I am not certain. I would say it all depends on whether or not the lady snail in question is already carrying unfertilized eggs or not. If she has a batch inside that is ready to go then she could lay them within a day or two. If she needs to develop the eggs then it would most likely take at least a week or two. I believe this is why they lay 3-5 batches like crazy then have a dry spell. They need to develop more eggs!. As I said I can't be certain, this is just a well educated hunch. Also keep in mind that males do mount and appear to mate with other males, so just because you see two "attached" doesn't mean one is a female and your about to have babies on the way. Thank you so much for your wonderful comments. The lack of info was exactly why I made this blog. I hoped to get at least a basic comprehensive layout of a good amount of the available information in one spot for those who just plain wanted to know more about these guys! :-) Hope this helps and thanks for stopping by!

  4. I have one gold mystery snail, had it for about 3 months. It kept laying eggs on the side of the tank, when there was about 7, I started taking them off as I thought they were ugly, and since I only have one snail, would never expect them to hatch. To my surprise, one of the clusters crushed and inside were heaps of babies! Live babies! Still have them. How is this possible? Like I said, I only had one snail.

    1. That is simple! This is one of the most amazing things about these creatures, they have the ability to store sperm for a year or more! So your little female goldy was kept in a tank with males, they mated and she stored the sperm until she was ready to lay eggs! Congrats on your babies! Thanks for visiting. :-)

    2. I have four adult Mystery snails and they are mating like crazy but aren't laying any eggs.

  5. i have two mystery snails a big blue and a black one, but even with these pics i still cant tell if they are male or female

  6. Hello everyone. I have a blue who recently laid a clutch of eggs. I was hoping they would hatch and we would have some babies but instead there are tiny worms coming out of them. It was very unsettling to see. Can someone please tell me what i need to do? Will these worms harm my fish and or snails? Please help.