Today the lamprey become...ammocoetes

Some of the little lamprey are moving right along, today I found my first ammocoete.

Here you can see it looks like an actual fish now, there is a clear head and a tail. And for those of my students you can easily see three of the defining features of chordates here (post-anal tail, notochord, pharyngeal slits). Th tiny black dot is the eye, this is a fairly undeveloped eye mostly good at detecting light or dark, not for telling that a giant eye is looking at you through a microscope.

The gut is really dark in this photograph because it is still filled with yolk. As the animal finishes development the yolk will disappear and the gut will be ready for real food to start coming in.

Although you cannot see it in the picture, under the microscope it is easy to watch the little heart beating away.

A closer look...

More time permitted me to take some close up pictures of the eggs and the pro-larvae.

Here is how they all start, the grid is 1mm x 1mm. Inside of these tiny balls is a little bit of yolk and some cells which assemble and make an animal body.

And here is what they become a tiny pro-larvae, sitting quietly and continuing to develop.

Here is a much closer image, each of the grids is a 1mm x 1mm box, so you can tell this guy is small. The head is actually the smaller end pointed down. The little black dots are individual pigment cells.

Least brook lamprey and the meaning of (their) lives

The end of the spring is coming, and the summer will start soon. In the meantime, least brook lamprey in Maryland have been spawning. As part of my research, I have been keeping and studying adult least brook lamprey. As part of their day-to-day they went about spawning in the holding tanks, and we are now trying to raise the eggs and ultimately the larvae when they hatch out.

Excitingly, the eggs are becoming pro-larvae, and in a few weeks they will be larvae.
Here are some of the pro-larvae laying on the sediment and soon they will be able to burrow.

Don't believe me that those things are alive? Here they are wiggling.

And with a scale (pull tabs are 1 inch long, in case you were wondering)!

Hopefully, some of the work this summer will lend itself to more blog posts...we'll see.