Apatosaurus is a genus of herbivorous sauropod dinosaur that lived in North America during the Late Jurassic period. Othniel Charles Marsh described and named the first-known species, A. ajax, in 1877, and a second species, A. louisae, was discovered and named by William H. Holland in 1916. Apatosaurus lived about 152 to 151 million years ago (mya), during the late Kimmeridgian to early Tithonian age, and are now known from fossils in the Morrison Formation of modern-day Colorado, Oklahoma, New Mexico, Wyoming, and Utah in the United States. Apatosaurus had an average length of 21–22.8 m (69–75 ft), and an average mass of 16.4–22.4 t. A few specimens indicate a maximum length of 11–30% greater than average and a mass of 32.7–72.6 t.
The Varanidae are a family of lizards in the superfamily Varanoidea within the Anguimorpha group. The family, a group of carnivorous and frugivorous lizards, includes the living genus Varanus and a number of extinct genera. Varanus includes the Komodo dragon, crocodile monitor, savannah monitor, the goannas of Australia and Southeast Asia, and various other species with a similarly distinctive appearance. Their closest living relatives are the anguid and helodermatid lizards.
Monitor lizards are large lizards in the genus Varanus. They are native to Africa, Asia, and Oceania, and one species is also found in the Americas as an invasive species. About 80 species are recognized.
Megalania is an extinct species of giant monitor lizard, part of the megafaunal assemblage that inhabited Australia during the Pleistocene. It is the largest terrestrial lizard known to have existed, reaching an estimated length of 3.5 to 7 metres, and weighing between 97–1,940 kg (214–4,277 lb), but the fragmentary nature of known remains make estimates highly uncertain. Megalania is thought to have had a similar ecology to the living Komodo dragon. The youngest fossil remains of giant monitor lizards in Australia date to around 50,000 years ago. The first indigenous settlers of Australia might have encountered Megalania, and been a factor in their extinction.
Ankylosaurus is a genus of armored dinosaur. Its fossils have been found in geological formations dating to the very end of the Cretaceous Period, about 68–66 million years ago, in western North America, making it among the last of the non-avian dinosaurs. It was named by Barnum Brown in 1908; it is monotypic, containing only A. magniventris. The generic name means "fused lizard", and the specific name means "great belly". A handful of specimens have been excavated to date, but a complete skeleton has not been discovered. Though other members of Ankylosauria are represented by more extensive fossil material, Ankylosaurus is often considered the archetypal member of its group, despite having some unusual features.
Tylosaurus is a genus of mosasaur, a large, predatory marine reptile closely related to modern monitor lizards and to snakes, from the Late Cretaceous.
Dysalotosaurus is a genus of herbivorous iguanodontian dinosaur. It was a dryosaurid iguanodontian, and its fossils have been found in late Kimmeridgian-age rocks of the Tendaguru Formation of Lindi Region in Tanzania. The type and only species of the genus is D. lettowvorbecki. This species was named by Hans Virchow in 1919 in honor of the Imperial German Army Officer, Paul von Lettow-Vorbeck. For much of the 20th century the species was referred to the related and approximately contemporary genus Dryosaurus, but newer studies reject this synonymy.
The emerald tree monitor or green tree monitor, is a small to medium-sized arboreal monitor lizard. It is known for its unusual coloration, which consists of shades from green to turquoise, topped with dark, transversedorsal banding. This coloration helps camouflage it in its arboreal habitat. Its color also makes the emerald tree monitor highly prized in both the pet trade and zoos alike.
Palaeosaniwa canadensis is an extinct species of carnivorous lizard from the late Cretaceous of North America. The name, given by Charles Whitney Gilmore in 1928, means "ancient Saniwa from Canada".
The peacock monitor, also known commonly as Auffenberg's monitor, is a species of small monitor lizard in the family Varanidae. The species, which belongs to the subgenus Odatria, is endemic to Rote Island, Indonesia.
The golden-spotted tree monitor, also known commonly as the golden speckled tree monitor, is a species of monitor lizard in the family Varanidae. The species is endemic to Waigeo Island in Indonesia.
The turquoise monitor is a species of monitor lizards found in Indonesia. Specifically, it is found on Halmahera Island and in the Maluku Islands.
The Ceram mangrove monitor, Varanus cerambonensis, is a species of monitor lizards found in Indonesia. Specifically, it is found on some of the central Moluccan Islands including: Ambon, Seram, Obi, Buru, and Banda. On Ambon and probably on New Guinea V. cerambonensis occurs sympatrically with Varanus indicus. It is in the indicus species group of the subgenus Euprepiosaurus.
Finsch's monitor is a species of monitor lizard in the family Varanidae. The species is found in New Guinea and Australia.
The Rennell Island monitor is a species of monitor lizards found in the Solomon Islands archipelago. It is also known as the Hakoi Monitor. It belongs to the subgenus Euprepiosaurus along with the canopy goanna, the peach-throated monitor, Kalabeck's monitor, and others.
The Palawan water monitor, Varanus palawanensis, is a quite large species of monitor lizard in the family Varanidae. The species is endemic to the Philippines.
Aiolosaurus is an extinct genus of monitor lizard from the Late Cretaceous of Mongolia. The type and only species, Aiolosaurus oriens, was named in 2000 from Ukhaa Tolgod, a rich fossil site in the Campanian-age Djadochta Formation.
Saniwa is an extinct genus of varanid lizard that lived about 48 million years ago during the Eocene epoch. It is known from well-preserved fossils found in the Bridger and Green River Formations of Wyoming. The type species S. ensidens was described in 1870 as the first fossil lizard known from North America. Several other species have since been added, but their validity is uncertain. It is a close relative of Varanus, the genus that includes monitor lizards.
Galeamopus is a genus of herbivorous diplodocid sauropod dinosaurs. It contains two known species: Galeamopus hayi, known from the Late Jurassic lower Morrison Formation of Wyoming, United States, and Galeamopus pabsti, known from the Late Jurassic fossils from Wyoming and Colorado. The type species is known from one of the most well preserved diplodocid fossils, a nearly complete skeleton with associated skull.
Varanus spinulosus, the Solomon Island spiny monitor, Isabel monitor, or spiny-neck monitor, is a species of monitor lizard. It is endemic to the Solomon Islands archipelago and is also known from Santa Isabel Island, San Jorge Island and Bourgainville Island.
