Brittlegill mushroom Russula mutabilis under post oaks ...

The image shows a close-up of an open mushroom with its underside visible, lying on top of dirt. The mushroom appears to be a type of Brittlegill mushroom (Russula mutabilis), which is commonly found in North America and Europe.

Here are some key features of the mushroom:

* **Cap:** The cap is not visible in this image as it has been removed from the stem, but based on the context provided, we can infer that it would have been a light brown or tan color with a smooth texture.
* **Stem:** The stem is short and stout, which is typical of Brittlegill mushrooms. It appears to be slightly darker than the cap and may have some small ridges or wrinkles on its surface.
* **Underside:** The underside of the mushroom has a white gills that are closely packed together. These gills are attached to the stem and curve downward, giving them a distinctive shape.
* **Spores:** Although not visible in this image, Brittlegill mushrooms produce small, yellowish-brown spores that are spherical or egg-shaped.

Based on these characteristics, it is likely that the mushroom in the image is indeed Russula mutabilis. However, without further examination or expert identification, it's difficult to say for certain. – AI vision