Shadow Insect
These insects have stolen the Spring Spirits' Light and entered that area into the Twilight. The only way to bring that area back to light is by destroying 16 of these little buggers. However, when you have to return the light to the spirit Lanayru, you can only get 15, after you get 15 the last one is located right above the Lakebed Temple. This is the location of...
The Shadow Bloat
Seemingly the mother of all the insects, it is a hideous creature. To defeat it, lunge at it after it dives at you. Bite at it around three times and it will fall onto its back. Charge and release an energy field to defeat it and get the last Light Tear.