Heloderma Fossil Scute Prehistoric Lizard Reptile Oligocene Cenozoic Collectiion (3)

Rare Fossil Scale Gila Monster Prehistoric Poisonous Lizard Primitive Reptile Heloderma sp. mm 2 x 1 Elodermi Sauri Squamata Oligocene Cenozoic Tertiary Collecting Paleontology Museum.

Difficult to find, fossil find of Osteoderma of the Bone Armor Plates of a "Gila Monster", coming from the Arikareean site (late Oligocene) of Brooksville 2 in Florida of excellent quality, with appreciable details very well preserved of the dentition and the portion maxillary.
Not restored at all. Only a piece, as in photos.

The fossils are found in fissures in the rock and have been interpreted as the inhabitants and prey of the animals that lived in the caves. The presence of bat fossils confirms the hypothesis that these fissures were part of a cave system.
All our material coming from this locality is part of the endemic microfauna, with most of the pieces measuring about 3 mm in length. Magnification is needed to properly visualize these fossils, but they are wonderful examples of an ancient cave environment of 28 million years.

Osteoderms or Dermal Scute are a protective structure present in a limited number of reptiles, including turtles, and in some groups of mammals.
The osteoderm is most commonly called Armor and is made up of Bone Plates surmounted by the dermis, which is in turn covered by the epidermal derivatives. Generally speaking, in zoology they are so defined all the structures generated by an hyper-production of keratin by the epidermis, namely: nails, claws, hooves, feathers, scales, horns, beaks, hairs, buns.

The lizards of the Helodermatidae family appeared for the first time from the fossil remains of the Cretaceous.
They are usually covered with small flakes, not overlapping, similar to spheres, with osseous osteoderms in the upper part of the body and are the only poisonous lizards. The family is mainly from the new world, although a distant relative, Estesia mongoliensis, was in Mongolia in the Cretaceous and Euheloderma gallicum briefly reached France in the early Oligocene (31-33 million years ago), probably through the Canadian Archipelago route through Greenland. The Lowesaurus matthewi species of the Oligocene of Nebraska (31-33 mya) was named in honor of Charles H. Lowe, herpetologist of the University of Arizona. Bhullar and Smith (2008) have instead found a fossil Heloderma of the first Miocene (23 mya) of Florida, which was interpreted as morphologically between Euheloderma and Heloderma. An interesting Heloderma was reported from the fossil oak forest of My-Pliocene (4.5-7 mda) of Tennessee (Mead et al., 2012).
The modern genus Heloderma dates back to the Miocene (23 mya) in the Big Bend of Texas, where a skull of an unusually small species was called Heloderma texana (Stevens 1977, Bhullar and Smith 2008). Before the western and eastern Sierra Madre elevations formed the Mexican plateau and cooler, more dry climates, the area was more tropical. There are many biogeographic links between the Chihuahua desert in Texas and the Mogollon Rim and the lower Grand Canyon in Arizona. It is therefore suggested that the descendants of H. texana have dispersed from the modern desert area of ​​Chihuahua to the north and west to evolve into the current Gila Monster (H. suspectum). Subsequently, the Heloderma disappeared from the mid-continent areas to the east, and the Gila Monster expanded southward from the modern Mohave desert (formed only 1 mya ago!) Through the Sonora desert to Southern Sonora.
There, in the deciduous tropical forest, Gila's monster met his distant tropical relative, the Mexican lizard H. horridum.