The species is not identified in this brief video, but its body habitus is that of an "inchworm," so it's a moth caterpillar - probably Eupithecia:
At least 6 of Hawaii’s described Eupithecia species are raptorially carnivorous, only 2 are known to feed predominantly on plant material, especially Metrosideros flowers. A diet including protein-rich flower pollen and a defensive behavior of snapping may have preadapted Hawaii’s ancestral Eupithecia for a shift to predation. Severe barriers to dispersal of mantids and other continental insect predators into Hawaii resulted in an environment favoring behavioral and consequent morphological adaptations that produced these singular insects, which can be commonly called the grappling inchworms.I was puzzled by the phrase "raptorially carnivorous," until the term was repeated later:
They have raptorial claws adapted for grabbing struggling prey, and long thin appendages on the tip of their abdomens which probably work somewhat like the trigger hairs in Venus fly-traps.And this is interesting -
Interestingly, some are host plant specific, even though they do not eat the plant, because they look so much like that particular plant and it gives them a great advantage in disguise. Some are even specific to the part of the plant on which they rest. One Eupithecia is specific to the green, living fronds of the native Hawaiian fern known as uluhe, and it is the perfect green to match their color. Another dark brown species is always found on the mats of dead fronds underlying the green, living part of the plant.They seem to handle parasitic wasps with ease:
Almost no parasitoids have been reared from Eupithecia caterpillars. It certainly seems likely that Eupithecia may be rarely parasitized because it is difficult for a parasitic wasp to sneak up on it and lay an egg without being caught. Here is a brief video showing lightning-fast E. orichloris capturing a parasitic wasp (and releasing it – apparently they are not very tasty).
To my knowledge, there is only one butterfly (the Harvester) that has a carnivorous larva - it feeds on wooly aphids.
Via Neatorama and Videosift.