Piranhadon titanus (Titanic Piranha-tooth), a massive predatory Fish in which the males are only 5-6 feet long and the females are frighteningly 20-50 feet long.* (deleted scene)
Estrivermis (Glutton-worm), a 15-20 inch long, needle-like, parasitic Worm.
Profanus (The un-holy), a 20-30 inch long parasitic Worm that is variety of Tapeworm.
Contereobestiolla (Frightening-little-beast), a 1-3 inch long, Earwig-like, parasitic Arthropod.
Cutiscidis (Skin-crab), a 1-4 inch wide, scab-like, parasitic, freshwater Crab.
Nefacossus fluvius (River Sin-slug), a 3 foot long, Arthropod-like Invertebrate that is descended from primitive Cephalochordates.
Neopedes, a group of aquatic Centipedes in which most species have gills instead of lungs.
Nepalacus (Lake-scorpion), an 8-16 inch long, Millipede-like Neopede.
Aspiscimex exos (Boneless asp-bug), an 18-23 inch long, predatory, Asp-like Neopede.
Hydruscimex maximus (Large Serpent-bug), the largest of the Neopedes. The Arthropod is up to 9-12 feet long.
Mortifillex venefecus (Poisonous Deadly-lure), a 3-4 foot long, Spiny lobster-like, predatory Neopede with a Fish-like lure to attract prey, such as Birds.
Scorpio-pede, Nepapede harpagabdominus (Grappling-hook-abdomen Scorpion-feet), an aggressively, territorial, herbivorous, 2-3 foot long, Scorpion-like Neopede. It is the only type of Neopede to have lungs instead of gills when it's an adult.* (deleted scene)
Impurucaris (Unclean-crab) .
Skull Island Pond Skater, an armored, predatory Pond Skater.
Skull Island Backswimmer, a large-mandibled, predatory Backswimmer.
Mosquitoes, Skull Island has countless species. Listed here are just 3 of the many kinds.
Skull Island Loggerhead, a Loggerhead subspecies that lives in brackish, shallow water.
Great Grey Heron, a species of Heron that eats small Reptiles (such as baby Foetodons). It looks very similar to the Great Blue Heron but not entirely.
Ambulaquasaurus cristarufus, a 10-14 foot long Dromaeosaur that usually hunts near waterfalls for Fish. One of its favorite food sources is the Sparklesides, catching some while shoals work their way upstream (similar to Grizzly Bears hunting Salmon).
Scissor-Head, Axiciacephalus curio, a 3-4 foot long, long-legged, wading, Heron-like, flightless Pterosaur with stumpy, little, useless wings.
Dinocanisaurus, a 3-4 foot long, aggressive, pack-hunting Cynodont.
Hylaeornis maximus, a common, medium-sized (4-5 feet tall to the hip) Ratite with a Great Hornbill-like head.
Noctupervagus pinguis, a nocturnal, 5-6 feet tall to the hip, Ratite with one hooked claw on each wing and teeth.
Pinnatono amarus, a large, 5-6 feet high to the hip, Moa-like Ratite whose chicks resemble the chicks of an Ostrich and like the Moa, it is entirely wingless. It also sprays musk from glands near its rear quarters to repel off predators.
Arachno-Claw, Arachnocidis, a large, 4-6 foot long, predatory, Spider-like Insect.*
Deplector, a predatory terrestrial Crab that ambushes its prey by hiding in the chasm walls. The females are 4-8 feet long and the males are only about half a foot long.*
Carnictis sordicus, a 7-13 foot long, predatory Worm.*
Vultursaur, Vultursaurus, a blind, nocturnal, flying Compsognathid that has Bat-like wings. Having Bat-like wings is unusual in Dinosaurs which normally have feathery Bird wings. The wingspan is 20-25 inches.* (briefly)
Abyscidis occisor, a 1-2 foot long, carnivorous, terrestrial Crab that resembles somewhat like a Eurypterid.
Terapusmordax obscenus, the largest of the flying Rat family (Volucerictiidae) with an 8-10 foot wingspan.*
Megapede impurus, a 3 foot long, upland-dwelling species of Megapede.
Skin-Bird, Cutisaves atroxoides, a medium-sized species of flying Rat with a 5-7 foot wingspan, but it is a glider rather than a flier. The reason for its name, "Skin-Bird", is because of its front teeth that point out and resembling a beak.
Chaly-Tops, Chalyceratops seradorsus, a 10-16 foot long, Chasmosaurus-like Ceratopsian.
Bifurcatops peritus, a 6-10 foot long, graceful, long-legged Protoceratopsid.
Arsartis, Arsarticaedes agilis, an 8-12 foot long, quadrupedel Dromaeosaur. Being quadrupedel is very unusual in Theropods.
Bidensaurus mactabilis, a 5-6 foot long, nocturnal, Tiger-like Gorgonopsid.
Gladiodon igneospinus, a fearsome, 8-18 foot long, striped Gorgonopsid with tall, red spines on its back that are used during the mating season.
Malevolusaurus perditor, a 20-24 foot long, omnivorous Sphenacodontid with a striking resemblance to Dimetrodon (which it is also descended from) and is also the biggest predator in the uplands.
Draco, Dracomicros hospes, a 9-12 inch long, striped species of gliding Lizard in the same subfamily (Agaminae) as the genus, Draco. It has 2 horns on its face and gives live birth.
Kong, Megaprimatus kong, a massive, 18-25 foot tall Great Ape with a striking resemblance of a Gorilla. Despite its Gorilla-like appearance, it is actually a descendent of Gigantopithecus from the mainland.