In The Cay, Phillip steps on a skate. What is a skate?

The skate that Phillip steps on while exploring the island and looking for Stew Cat is a fish that resembles a stingray. It is smaller than a stingray and has barb-like protrusions on its back for protection.  Skates are usually found in deeper water and lay eggs. Stepping on the skate is just more sign of bad luck for Phillip and Timothy who worry about the “jumbi” (bad luck) that has followed them onto the island.  Timothy is very superstitious and blames the bad luck on Stew Cat, but Phillip needs Stew Cat and doesn’t want to lose him.  After fending off the bad luck with a wooden, spiked replica of Stew Cat that he makes, Timothy finds the runaway cat at the end of Chapter 11 and tells Phillip that he believes their luck will change.