You can see the head and antennae sticking out of the long brown tube? That is a caddisfly larva in its portable case! Caddisflies are very cool insects who, in the larval stage, make themselves little cases in which to hide. Some are simple like this, just a plain tube. Others are large and all manner of things are attached to them, bits of twigs, pebbles, small shells, etc. This one was only about one inch long. Most caddisflies like faster flowing water, but this one was, for some reason, in a small puddle, filled with algae (which gives this the yellow colouration). The little white creature, looks like a springtail of some sort(Collembola), maybe a larva?