Arrow Worm (Sagitta spp.)

Tidepool Tim says, “Chaetognatha, arrow worms, include almost 200 species! About a fifth of them are benthic, living in relatively shallow water. Those are usually transparent. They look like arrows because they have two laterally paired fins to compliment their caudal fin. They got their name Chaeto-“gnatha” because of their protruding hooked jaws. They capture copepods and fish larvae with these jaws, rising to the surface at night to follow prey. They sink back down to the safety of the ocean floor during the day.”