A leopon /”LEP-uhn”/ is a hybrid resulting from the crossing of a male leopard with a lioness. The head of the animal is similar to that of a lion while the rest of the body carries similarities to leopards. These hybrids are produced in captivity and are unlikely to occur in the wild.
Many leopons have been bred in captivity. Best known are those born at Koshien Hanshin Park in Nishinomiya, Japan in the late fifties and early sixties, one of which survived more than twenty years. This is longer than would be usual for a leopard (maximum recorded life span in captivity 23 years) or a lion, which has an average captive life expectancy of 13 years. A litter of 2 hybrids was born in 1959 and 3 more were born in 1962. In captivity, the normally solitary male leopard remained with the family.
Unlike lions, leopons are good climbers. They also enjoy water, which often distresses their lioness mothers. Leopons are nearly the size of a lion, with stout bodies, but their legs are shorter, like a leopard’s. They have brown spots, paler than the leopard’s black spots, and tufted tails, like a lion. The base color is pale reddish yellow. Mature males have sparse manes about 8 inches (20 cm) long.
Diadophis punctatus, commonly known as the ringneck snake or ring-necked snake, is a species of colubrid snake. It is found throughout much of the United States, central Mexico, and south eastern Canada. Ring-necked snakes are secretive, nocturnal snakes that are rarely seen during the day time. They are slightly venomous but their non-aggressive nature and small rear-facing fangs pose little threat to humans who wish to handle them. They are best known for their unique defense posture of curling up their tails exposing their bright red-orange posterior, ventral surface when threatened.
Dorsal coloration is solid olive, brown, bluish gray to black, broken only by a distinct yellow, red, or yellow-orange neck band. Head coloration tends to be slightly darker than the rest of the body with tendencies to be blacker than grey or olive. Ventrally the snakes exhibit a yellow-orange to red coloration broken by crescent shaped black spots along the margins
Ring-necked snakes use a combination of constriction and envenomation to secure their prey. The snakes do not have a true venom gland, but they do have an analogous structure called the Duvernoy’s gland derived from the same tissue.
Ring-necked snakes first strike and then secure the prey using constriction. Next they maneuver their mouths forward ensuring that the last maxillary tooth punctures the skin allowing the venom to enter the prey’s tissue. Ring-necked snakes are rarely aggressive to larger predators suggesting that their venom evolved as a feeding strategy rather than a defense strategy. Rather than trying to bite a predator, the snake winds up its tail into a corkscrew, exposing the brightly colored belly.
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The 3 main types of hip joint in tetrapods.
Typical of reptiles, dinosaurs & mammals, and rauisucians respectively.
older vs modern reconstructions
Helicoprion (“Spiral Saw”) was a long-lived genus of shark-like cartilaginous fish that first arose in the oceans of the late Carboniferous 280 million years ago, survived the Permian-Triassic Extinction Event, and eventually went extinct during the early Triassic, 225 million years ago.
The only fossils known are the teeth, which were arranged in a fantastic “tooth-whorl” strongly reminiscent of a circular saw. It was not until the discovery of the skull of a relative, Ornithoprion, that it was realized that the tooth-whorl was in the lower jaw. The tooth-whorl represented all of the teeth produced by that individual in the lower jaw, in that as the individual grew, with the older, smaller teeth being moved into the center of the whorl by the appearance of larger, newer teeth. Comparisons with other eugenodontids suggest that Helicoprion may have grown up to 10-15 ft (3-4 m) long.
The exact location of the tooth-whorl in the lower jaw is an open debate. Older reconstructions placed the whorl in the front of the lower jaw; however this would create drag, making the shark a less efficient swimmer, and turbulence, alerting prey of its approach. A more current and scientifically accepted reconstruction places the whorl deeper into the throat. This arrangement would be best suited for soft bodied prey.
Coloured modern reconstruction illustration  by Mary Parrish
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The Armadillo Lizard (Cordylus cataphractus) is a lizard endemic to desert areas of southern Africa. It is also known as the Typical Girdled Lizard, Armadillo Girdled Lizard, Golden Armadillo Lizard, and Armadillo Spiny-tailed Lizard.
The Armadillo Lizard possesses an uncommon antipredator adaptation, in which it takes its tail in its mouth and rolls into a ball when frightened. In this shape it is protected from predators by the thick, squarish scales along its back and the spines on its tail. This behavior, which resembles that of the mammalian armadillo, gives it its English common name. This behavior may have inspired tales of the mythical creature Ouroboros.
Galerie de paléontologie et d’anatomie comparée, Paris
Strong contender for my favourite species.