Tuesday, August 5, 2014

Mangrove Box Jellyfish

Hello, I do apologize for the gap in my blog posts. I've recently moved to Boca Raton Florida. I've been up and down the beaches looking for jellyfish all over. I've found a few. There are mostly Comb Jellies and Upside Down jellyfish here. I did find one other species, the Mangrove Box jellyfish (Tripedalia cystophora).

These are some seriously cool jellyfish. They are small box jellies that have bell lengths of about 1 inch maximum. Their tentacles may stretch and additional 1-1.5 inches. Their sting is not very powerful. Some people describe a definite burning or itching and others feel nothing at all. I've personally not felt much, but I credit this to my common handling of jellyfish. Tripedalia have four eyes at the bottom of their bells. They can use these eyes to sense solid objects in from of them. I tested this by placing a hand in front of one. It was heading straight towards my hand and turned away, dodging it. Impressed, I tried it over and over. The same reaction occurred. We are dealing with some "smart" jellyfish here.
Tripedalia cystophora with full extended tentacles. 

 I've caught quite a few and had the chance to study them a little. The adults are obvious as they are colored orange. The orange color comes from the planula or reproductive material they hold. Females hold planula until they are mature. This means you can find a single mature female and start a polyp culture. I started my own culture of polyps. These jellies are invasive and breed very easy. They planula settle anywhere and very quickly (1-2 days). Unfortunately the polyps are very tiny. A stereo microscope helps a lot. I'm still currently working with the polyps.
Microscope image of the polyps. At most, I've seen the polyps grow 4 tentacles. 

These jellies are picky eaters. The wild caught specimens don't react much to common jellyfish foods. I tried baby brine shrimp, adult brine shrimp and multiple dry fish larva foods. None of them really worked. I noticed a few jellies ate very fresh baby brine shrimp. After a few discussions with other aquarists, I found a little more on their diet. The wild jellyfish are used to eating wild Copepods. They hunt these pods down actively. Wild caught specimens will likely need Copepods. Captive bred specimens can be fed brine shrimp and are raised a lot easier. So the best thing to do is grab some jellies and use them to start a polyp culture.

The white pouches running up the bell contain reproductive tissues.