Delphinidae (dolphin, killer, pilot and relations), 37 species. All images from acsonline.org. Ziphiidae (beaked whales), 23 species. Physeteridae (sperm whales), 1 species. Platanistidae + others (river dolphins), 4 species. Phocoenidae (porpoises), 7 species. Monodontidae (narwhal and beluga), 2 species. Kogiidae (pygmy and dwarf sperm whales ...