Reef worm id

Checked out my tank tonight and found something swimming in the water column near the top. I thought it was a small missing fish in my tank, but I was able to capture it and examine it. It turns out it was a worm, but it does not look like the typical bristle worms that I have seen before over the years. Its movement in the water was not the same as when I have seen bristle worms spawn in open water. I have these two photos, so maybe someone knows what kind it is.

The top portion is white and the lower portion is red. Both are feathery all the way to the center. It has two antennia. There is a prodomenant vein running down the center that you can watch the blood pulse through it. It really looked more like a small slender fish than a worm swimming in the water.

Nothing like something cool and unusual to spice up the evening.









Edited by WhiteReef - November 16 2011 at 11:00am

I added two vidoes of it swimming. The first one it gets sucked into the powerhead and survives. The second one is just where it is swimming.

Since I have not had issues related to it or that I know of, I put it back in. I just don't know if it was from the Florida LR/LS or from a frag.

How big is it? It looks long. It isn't shy that's for sure! I cannot wait until someone identifies it.

Looks like a fireworm to me.

My guess is it is a Free swimming Epitoke!


Epitoky is a form of reproduction observed in polychaete marine worms. The worms undergo a partial or complete transformation into an epitoke, a pelagic morph capable of sexual reproduction.

Often an epitoke is the posterior part of the worm, which separates from the anterior part (called the atoke); gametes are produced inside the epitoke. The epitoke may also form by asexual budding from the posterior.

There are two methods in which this can occur, epigamy and schizogamy. In epigamy, the whole worm transforms into a swarming epitoke. It rises and sheds its eggs and sperm. After reproduction, it dies. In schizogamy, the sexual forms are budded from the posterior or from the parapodia to swarm. This is effectively asexual reproduction of the epitoke.

In the third form (characteristic of Nereidae, for example), the whole worm becomes an epitoke. This form may be accompanied by partial or full degeneracy of digestive organs (causing the animal to die quickly) and enhancement of motor and sensory organs; in particular, whereas in its nonreproductive form the worm is a crawling animal, when it becomes an epitoke the worm develops swimming appendages, such as broad parapodia with paddle-shaped chaetae.

Epitokes swim to the plankton-rich surface region, where the gametes erupt from the body and the larvae hatch. This action is often synchronized with moon cycles, and epitokes swim in swarms.

In the past it was thought that epitokes were separate species from polychaete marine worms.