Original description on Flickr:

Periodically, I try to get decent photos of S. pumilis and as it's the wet time of year, they come up through the leaf litter, making them easier to find and photograph. So I've been sat on my lawn, between downpours and turning over hundreds of leaves....

They are really tiny, at most, 0.5mm so although common, they can be quite tricky to find. If you want to photograph them, and you think you might have found one, there's a few ways to tell until you get your camera to it. First is the colour. S. pumilis is anything from light grey yellow to a dark reddish orange. So sometimes, very distinctive, other times, not.

Shape. Seen from the top, it does have a rounder shape than a lot of the common springtails, for example, S. aureus, which is distinctly pear shaped. But the main thing I do is to check for the colour of the ocelli/eye patch. (All with a loupe, by the way!) Sharply black, not S. pumilis. Anything less distinct, small and/or with a reddish cast, probably S. pumilis.

This chap was around 0.4mm, shot at about x11, sat on the central vein of a fallen leaf.