When importing images, what is the little green box in the bottom right with a # in it?

Hi everyone,

When using RC and importing a bunch of images, a few dozen (out of a few hundred) have a little green box in the bottom right hand corner of the image in RC that has a number in it. The number ranges from several thousand to single digits. Most of the images have no number. What is that box and number?

Thanks for the help.

Hi jrivonlab,
green dot means that the image is aligned in the component. The number for selected image it is a number of founded features in that image and for not selected images it is a number of the features matches with selected image.
image