Modern dolphins have rounded heads housing their echolocation apparatus. This newly discovered species had a really exaggerated "melon" and forehead. A fisherman named Albert Hoekman pulled up the first known remains of the animal now called Hoekman's blunt-snouted dolphin. Living in what is now the North Sea, it was 6 meters long and possibly ancestral to today's pilot whales.
COMMENT: It looks to me like nothing so much as a dolphin wearing a "Gazoo helmet," sometimes used by American football players who have had concussions or collision-induced migraines. Presumably, the dolphins didn't play football.