The Harte Research Institute (HRI) has issued a warning about a group of stunningly blue sea creatures that are turning up on Texas beaches. The creatures, which resemble tiny dragons, can deliver a powerful sting if they are touched. They are a species of sea slug called blue glaucus, which feeds on the tentacles of the Portuguese man o' war and store the stinging cells in their appendages to release if they feel threatened. HRI warns that these creatures can be difficult to see on a beach due to their size and are usually found floating in the ocean.