Not to be confused with Pearl, the current SeaWing royal treasurer.
Queen Pearl was a royal female SeaWing and Prince Fathom's sister. She was the only known Seawing Queen to have ascended to the throne without killing the previous Queen. She was able to do this because Albatross killed the previous queen and any other heirs to the throne, therefore she was left in charge. Her first decree as queen was to outlaw the use of animus magic anywhere in the Kingdom of the Sea, since her grandfather, Albatross, went insane from overusing his abilities and subsequently slaughtered practically her entire family. She forced her brother to swear to not have any children with Indigo as one of them might have turned out to be an animus. The only reason she survived was that she cut herself with broken shards of glass so that Albatross thought she was already dead. Fathom broke his oath to her when he had to put Darkstalker in an eternal sleep, and again in order to free Indigo. She was mentioned in Moon Rising when Moon researched about dream visitors in one of the scrolls at Jade Mountain Academy's library. Earlier in the book, Darkstalker (Legends), she was described to "glitter with coils of gemstones, long twisted ropes of pearls and opals and sapphires circling her torso and ankles."
In Darkstalker Legends, it described Pearl as, "glittered with coils of gemstones, long twisted ropes of pearls and opals and sapphires circling her torso and ankles" 
Pearl was the sister of Fathom and one of the dragonets chosen for animus testing, later becoming the Talons of Power ceremony. She tried to shush Indigo multiple times as they waited, and was the one to point out that it was Fathom's coconut that had hit Albatross.
During The Royal SeaWing Massacre, she used the glass from the shattered aquariums to cut herself, covering her in blood. This caused an insane Albatross to walk right past her, believing she was already dead. After Albatross was killed, she emerged from her hiding place and claimed her role as queen of the SeaWings. Her first decree was to outlaw animus magic throughout the kingdom. Her brother, Fathom, made a blood oath, promising to never to use his magic again, and to never have dragonets, which meant that he had to stay away from Indigo, for she knew that she was the only dragon who he'd use his magic for. She appointed Indigo to be her head guard.
Around a year later, her cousin, Current, returned from being held in the Night Kingdom. He reported that the NightWings had an animus and that he was overusing his powers. To avoid a similar tragedy happening in their kingdom, she sent Fathom; along with Indigo, Wharf, and Lionfish; to the Night Kingdom, and assigned Fathom to train the animus and warn him of the price of using magic.
It is unknown what happened to her after the events of Darkstalker (Legends).
Present: Abalone • Flounder • Herring • Herring's Brother • Kelp • Lagoon • Nautilus • Pearl • Piranha • Riptide • Snapper • Squid • Tempest • Tortoise • Urchin • Webs • Whirlpool