One of my students is examining reproductive schedule in Whitetail Shiners from the Flint River in north Alabama. He's found some kind of parasite attached to the gonads of several fish from last August, both male and female. The first photo below is a relative close-up, the second photo shows most of the gonads with the site of this parasite circled in white. I'm hazy as to what this is; I'm inclined to think to think it's some kind of fungus with a central mycelium with hyphal threads in blue-green running out? That could be crazy, of course, but this is new to us. I'm open to any IDs if you feel so moved, thanks. We've already found Acanthocephalans in gonadal tissue, along with Lernea parasitic copepods anchored behind pelvic fins. Whitetails seem to be a mess compared to other cyprinids we've looked from the Flint.

Not that I have a clue Bruce, but it looks mobile. Is it?

It doesn't seem to be. We found them in formalin-fixed fish, and the apparent threads go in to the gonadal tissue.

Bizarre. Even more so that the color was preserved. Would it be possible to separate and examine under the microscope for cell structures?

Yeah, that's our task for next week, trying to get one or more these mounted in Kleermount and photographed under a compound 'scope. If it's fungal, that should be fairly obvious at the cellular level.