Unknown marine organism

pwnell · Post by **pwnell** » Thu Feb 07, 2013 5:55 pm

Found another weird thing in my reef aquarium. It attaches to the live rock / coral and seems to be filter feeder. I did discover nematocysts on its tentacles so it seems to sting its prey. I also found diatoms in its stomach. They seem to be colonial as I have never found them alone.

First a (close to) 1:1 macro shot of the organisms in their natural environment:

Under the microscope under dark field illumination (4x) they look quite different:

A single polyp with a 10x objective, dark field:

41-image stack with 10x objective, 1.6x magnification, DIC

Single image, 20x objective, DIC

Finally, to show the contents of its gut, here is a photo under fluorescent excitation (UV/Blue), 40x objective. The red stripes are diatoms, not sure what the green blob is and also not sure why its oral disk fluoresces yellow.

rjlittlefield · Post by **rjlittlefield** » Thu Feb 07, 2013 10:12 pm

Possibly one of the "moss animals", Ectoprocta. Details are different from the fresh water species I'm familiar with, but the general body shape and habit look similar.

--Rik

Jacek · Post by **Jacek** » Thu Feb 07, 2013 10:40 pm

beautiful

Ecki · Post by **Ecki** » Fri Feb 08, 2013 3:26 am

Great darkfield shots!

Bruce Taylor · Post by **Bruce Taylor** » Fri Feb 08, 2013 8:45 am

Not my bailiwick, but...they look Hydrozoan, to me. Some kind of Obelia, maybe? Pennaria? Halecium? There seem to be a million flavours.

A key to the sessile hydrozoa: http://hermes.mbl.edu/publications/biob ... /pdf/2.pdf

naturephoto1 · Post by **naturephoto1** » Sun Feb 10, 2013 6:38 pm

Waldo,

Beautiful, well done work and images.

Rich