An octopus. In particular ... clearing sand from beneath the lip of the shell. There’s now a small gap between shell and seafloor. In the gap, the eyes reappear. You bring your mask close ...

But their adorably small size and Instagrammable appearance is deceptive ... Mike Workman/ Shutterstock There may be around 10 different species of blue-ringed octopus, though only four have been ...