A Choanoflagellate and Lacrymaria

[dy5]

A couple of photos of creatures living in my neighbor's backyard pond.

The first is a group of choanoflagellates, possibly Salpingoeca sp., sitting on a spherical algae, Golenkinia sp. (I think). A quick bit of research turned up that the choanoflagellates share a common ancestor with all multi-cellular creatures making them well-studied by evolutionary biologists. If anyone's interested, there's basic information here: https://www.cell.com/current-biology/fu ... 05)00142-9 The creatures are very common, but I hadn't noticed them until they started showing up sitting on the algae spheres. Is it weird that I think they are really cute?

The second image is from my first encounter with Lacrymaria. There are fascinating videos of this creature, including the award-winning video by Charles Krebs. However, they are even more spectacular and bizarre in person. Given the animal's thrashing around, it was sheer luck to get a frame with the mouth and almost all of the neck in focus.

Both photos taken with DIC and high-speed flash.

[dy5]

Adding a photo to show the length of the choanaflagellate flagellum (hence the odd orientation). Also this one had just ingested its lunch.

[rjlittlefield]

These are lovely!

--Rik

[dy5]

Thanks!

Cheers, David