Snail ID help please: Pyramidellids or Rissoids

fatoldsun · Mar 20, 2012

I have several of these small white (tan-ish) snails and I'm trying to ID them as Pyramidellids or Rissoids. I broke out the microscope and tried to take some pics as an article suggested that Pyramidellids (the evildoer of the 2) has heterostrophic shell coiling, they apparently have no operculum and the inner edge of their shell apertures have a "fold". Well I read and re-read the description of heterostrophic shell coiling and I don't get it so maybe someone can look at my pics and offer an opinion. Oh, for the record, I've seen these for well over a year. I have no clams and never seen them on a foot of any of my (invited) CUC snails. It seems that Pyramidellids will die out without a food source and Rissoids eat algae and detritus -so good bit my look at these pics points to Pyramidellids but if I'm correct what are they living on?

Ok here's a shot to show scale. This dish is maybe 2" in diameter...

Here's the operculum or lack of...

And the best shots I could get of the coiling

Thoughts?

Baxreefs · Mar 20, 2012

Pyrams are a pain!

Do you have any clams? squammys and max are thier favorite targets followed by crocea and smaller deresa.

They will go for your astrea and come snails as well and often come in to your tank on these CUC snails.

Use a soft tooth brush and inspect and brush each snail and clam that you can get your hands on every day . You have to remove the animal, brush then rinse in sepreate container as these little buggers stick to everything.

Heavily infested clams can be dipped in Lugol's or iodine baths as well.

GL!

Edit: .....

I see you have no clams, they are on your CUC snails. Keep looking...

downbeach · Mar 20, 2012

Definitely look like Rissoid, this may help:

And an article:

http://reefkeeping.com/issues/2008-02/nftt/index.php

fatoldsun · Mar 20, 2012

Thanks Jim!! - the "diagram"? was a huge help - I could not visualize what was meant by the fold or the heterostrophic coiling. All I had to go on was that I would find them on the glass or occasionally on a rock (but they're hard to find) so I was hopeful but this puts my mind at ease. I also hadn't seen the "crossed ridges piece - the microscope definitely shows that. Now off to read the article you posted (instead of working....)
I do know if I ever take the plunge and get a clam I'll be on the look out - I'm scared straight.... the thought of trying to rid the tank as Bax described did not sound like the pleasure and relaxation I strive for with reefing

twisted · Mar 20, 2012

I dealt with pyramids for a year( I had tons!) I finally won with a sixline and a coris wrasse. It's been two years and I haven't seen another. They ate at my zoas and palays, and infested my snails. I spent hours a day picking and scraping eggs, to no avail. They can really b a pia if unnattended

Twisteds 180 Reef

fatoldsun · Mar 20, 2012

so if I assume that I am up against rissiods and not the pyrams I wonder if there's any downside to the rissiods - my palays and zoas always seem to struggle and I always blame the Singapore Angel even though I've never caught him in the act and the palays are small and alive - if it was the angel I'd think they'd be gone - they're not gone but not growing either. could it be the rossiods? and if a 6-line will go after the pyrams. I wonder if my 6-line will go for the rissiods...

twisted · Mar 20, 2012

Not familiar with rissoids but I agree that's what they look like. Have you bought any corals or snails from ocean? Their turbo snails and zoas are infested with pyrams. Maybe u have both?

Twisteds 180 Reef

twisted · Mar 20, 2012

My sixline eats ceriths and any small snail it can suck ouuta the shell

Twisteds 180 Reef

Hawkeye · Mar 20, 2012

Those are some amazing pics! You could send them to Dr. Ron Shimek if you want (on your own dime) and if he has time he could make a 100% accurate assessment. He has his own forum on marine depot.

i was under the impression pyrams are parasitic and attack only snails or clams. not both. I have never heard of them attaching corals.

fatoldsun · Mar 20, 2012

All my CUC came from aquarium center in blackwood or an online purchase I made when I was first starting. Not sure I remember where that was but it was out of state. Funny about your 6-line. I have a madarin about to come out of QT and I'm hoping the 6-line doesn't terrorize it but the 6-line is so fat it looks pregnant so hopefully there's enough food to go around for them both

twisted · Mar 20, 2012

They are know to cross over to other species. When I had them they did alot of damage to certain polyps such as people eaters, watermelons and my fire and ice zoas. I watched as they literally sucked them dry. Especially as my snail pop started to dwindle. It was a plague

Twisteds 180 Reef

twisted · Mar 20, 2012

My six will only let a spotted mandarin in, it killed my psychedelic one. And its a six foot tank, I pray every night for him to go carpet surfing...lol

Twisteds 180 Reef

fatoldsun · Mar 20, 2012

Hawkeye said:
Those are some amazing pics! You could send them to Dr. Ron Shimek if you want (on your own dime) and if he has time he could make a 100% accurate assessment. He has his own forum on marine depot.

i was under the impression pyrams are parasitic and attack only snails or clams. not both. I have never heard of them attaching corals.

Thanks
The recognition makes dealing with my wife making fun of me worthwhile - I guess I can't blame her when the hobby has me trying to use my phone to take eye-piece pics from the microscope set up on the kitchen counter.

fatoldsun · Mar 20, 2012

twisted said:
My six will only let a spotted mandarin in, it killed my psychedelic one. And its a six foot tank, I pray every night for him to go carpet surfing...lol

Twisteds 180 Reef

Well I'm gonna try to introduce a green (psychedelic) and it's a 4' tank. *GULP*. guess I better not point out the mandarin to the kids until I see if it makes it. 6-lines only been in there a month or 2 so it's not totally in charge yet...

twisted · Mar 20, 2012

I've seen lots of tanks with both and no probs. mine is just a nasty little sucker. If I ever catch him, he's gonna take a swim with my angler and lion fish

Twisteds 180 Reef

discordipinna · Mar 22, 2012

I had an army of rissoids before my tank crash. I never saw them hurt anything, just clean the rocks and glass. Your pictures match mine pretty exactly, so I'm sure yours are rissoids. I really don't think you need to worry about them hurting anything.

I actually wish I'd been able to save some of them. I like having lots of snail diversity.