Thursday, April 5, 2012

Mysterious Polyp Appears!

A few weeks ago I was examining my 20 gallon moon jellyfish grow out tank. I noticed a lone polyp living on a piece of sea weed in the tank. Naturally, I extracted it from the tank and put it in a dish. At first I assumed it was a moon jellyfish polyp that had some how made its way into the tank. This was very possible, polyp tissue is sometimes left over from ephyra and may develop into a polyp. But I later realized the polyp was growing on some seaweed that was in a bucket with 4 cannonball jellyfish when I was at the beach. This left a great chance of it being a cannonball jellyfish polyp now. This got me excited and so I put it, still attached to a chunk of seaweed, in its own petri dish.

Average Moon jellyfish polyps.
I examined the polyp further, to find any differences between it and the moon jellyfish polyps I have. I noticed the mouth structure of the mystery polyp was more elongated and almost tube like. Moon jellyfish polyps never seem to have this mouth structure, but rather a flat hole as a mouth. The mystery polyp also seemed to be shaped very slightly different, and was slightly larger than the average moon polyp.
The mysterious polyp, before being removed from the tank. 

That being said, by all means the polyp could still be a moon jellyfish polyp. studying such tiny organisms is hard and many changes can easily occur between two induviduals. This makes it hard to judge the species. So in order to truly find out the species i will need to wait for the polyp to strobilate. If I have to I can grow out a mystery ephyra and see what it produces. But I found an interesting observation on polyps by a scientific article. In a study done on cannonball jellyfish, the polyps were found to produce only 1-3 ephyra per strobilation, often two. The article also explains that they had trouble raising the polyps as their water quality declined fast. My water quality is very consistent, as I buy stabilized ocean water for my polyps and ephyra. That could lead to more ephyra.

So the polyp has begun to strobilate. Almost perfectly the mystery polyp and a moon polyp are strobilating at similar times. The moon polyp is about a day ahead. I've noticed the mystery polyp is a little slower, but that could be due to several variables. The mystery polyp also started with 2 cleaves and has grown to 4-5 (a cleave is referring to the cleavage in a polyp where it begins to form disks and each disk is a jellyfish).

The next few days may be critical in deciding if it is a cannonball jellyfish polyp or just another one of my moon jellyfish polyps. If I cant tell from the strobilation the ephyra should begin to look very different from a moon ephyra within a few days. Moon jellyfish and cannonball jellyfish are vastly different. I find it strange how they look so similar at these stages.


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