ID Help

[seanm001]

First time SW / Reefer here, looking for some help in identifying some LR hitchhikers.

First, I noticed a couple of small worms, dark reddish-brown in color, in the sand. Maybe a quarter to three-eights of an inch long and no thicker than a piece of cotton thread. They're photosensitive and contract when I shine a flashlight directly on them.

Second, I saw what appeared to be a shed exoskeleton floating through the water column and I thought it came from some kind of shrimp. But then I saw the organism running around on top of the sand. It was maybe and eighth of an inch long, clear to whitish, had a head with antennae on it, kind of long and low like a worm, but it didn't appear to have as many legs as a bristle worm. Honestly, it looked to me a lot like the pictures I've seen of amphipods, but I was under the impression they float around in the water column, not run around on the substrate.

Lastly, I found this cruising up the side of the tank:

Shot from out side the tank

Looking down into the tank

Looking down into tank (flash on)

It's about a quarter inch in diameter, the shell is conical in shape (not spiralled like a snail), an off-white color with brown patches on it. It's almost like a shield on its back. You can see antennae in the shot using the flash. It hustled up the side of the tank and hung out right at the water line. I was doing some work in the tank I it got knocked down onto the substrate where it laid upside down until I righted it.

Sorry I only have pics for one of them, the others were too small or too fast to get any recognizable shots of them.

Thanks,
Sean

 

[pagojoe]

The animal in the pic is a snail, and is a "limpet" of some sort. It's probably a fissurellid, either a keyhole limpet or a related species. I can't tell if it has a hole at the apex, or a slit somewhere else on the shell, from your photos. If it does, it is definitely a fissurellid. It may also be a true limpet, in which case it will be an algae eater, and will have no hole at the apex nor anywhere else on the shell.

Cheers,



Don

 

[bigtex52]

I concur about the picture being a limpet. As far as your possible amphipod, it does sounds like an amphi to me. Although they CAN swim up into the water column, mine run around over the substrate and rock like a bunch of little silver/grey weasels with their tails tucked under them. Kinda neat to watch.