Varanus marathonensis Temporal range: Miocene, | |
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Vertebrae and skeletal restoration of the "V. amnhophilis" holotype | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Order: | Squamata |
Family: | Varanidae |
Genus: | Varanus |
Species: | V. marathonensis |
Binomial name | |
Varanus marathonensis Weithofer 1888 | |
Synonyms | |
List
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Varanus marathonensis, the Samos dragon, is an extinct species of monitor lizard from the middle to late Miocene of Greece and Spain, known from several specimens. A specimen consisting of a partial skull and several vertebrae was named Varanus amnhophilis in 2012 and placed in its own subgenus, Varaneades, but a 2018 study found it to be a junior synonym of Varanus marathonensis. [1] Comparisons with other species of monitor lizards put its size between 60 and 80 cm (2.0 and 2.6 ft) in length. The fossil was found in the Turolian-age Mytilini Formation on the island of Samos and is currently housed in the American Museum of Natural History. [2]
Varanus marathonensis is known from several specimens. One nearly complete specimen from Cerro de los Batallones, Spain, is currently the most complete fossil of any Varanus species yet discovered. [1]
Another specimen originally described as "V. amnhophilis" is known from several bone fragments, including the right side of the braincase, a right quadrate bone, part of the palate and skull roof, the right coronoid process and glenoid region of the lower jaw, a piece of the clavicle, and five vertebrae. [2]
These bones were found by American paleontologist Barnum Brown, who stored it in the mammal collections of the American Museum of Natural History. The specimen was not identified as a reptile until 2009. Mammal paleontologist Nikos Solounias, who has worked extensively on Samos Island fossils, then brought the fossil to the attention of Carl Mehling. Mehling removed the specimen from the fossil mammal collection and cataloged it as AMNH FR (fossil reptile) 30630. [2]
The specimen was described in 2012 as a new species of Varanus, and was placed in a new subgenus called Varaneades. The species name amnhophilis means 'lover of lamb', from the Greek αμνόζ (amnhos, 'lamb') and φιλiζ (philis, 'a lover of'), as a reference to the diet of the largest living monitor lizards, which often includes sheep-sized (and larger) mammals. The subgenus name Varaneades comes from the genus name Varanus and the Neades, mythical nymphs from Samos. [2]
A subsequent study in 2018, however, found V. amnhophilis to be a junior synonym of V. marathonensis. [1]
The body length of AMNH FR 30630 was estimated by comparing the length of the braincase and an individual vertebra with their lengths in living species of monitor lizards. The ratios of braincase length to postcranial length and dorsal (back) vertebra length to postcranial length are very similar for many monitor species, and were used to estimate the postcranial length of V. amnhophilis. The first ratio gave an estimated postcranial length of about 71.26 cm (2.338 ft) and the second gave a length of about 66.45 cm (2.180 ft). [2]
The Varanidae are a family of lizards in the superfamily Varanoidea and order Anguimorpha. The family, a group of carnivorous and frugivorous lizards, includes the living genus Varanus and a number of extinct genera more closely related to Varanus than to the earless monitor lizard (Lanthanotus). 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 earless monitor lizard and Chinese crocodile lizard. The oldest members of the family are known from the Late Cretaceous of Mongolia.
Monitor lizards are lizards in the genus Varanus, the only extant genus in the family Varanidae. 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, but the fragmentary nature of known remains make estimates highly uncertain. Recent studies suggest that most known specimens would have reached around 2–3 m (6.6–9.8 ft) in body length excluding the tail, while some individuals would have been significantly larger.
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" or "bent 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.
Seymouria is an extinct genus of seymouriamorph from the Early Permian of North America and Europe. Although they were amphibians, Seymouria were well-adapted to life on land, with many reptilian features—so many, in fact, that Seymouria was first thought to be a primitive reptile. It is primarily known from two species, Seymouria baylorensis and Seymouria sanjuanensis. The type species, S. baylorensis, is more robust and specialized, though its fossils have only been found in Texas. On the other hand, Seymouria sanjuanensis is more abundant and widespread. This smaller species is known from multiple well-preserved fossils, including a block of six skeletons found in the Cutler Formation of New Mexico, and a pair of fully grown skeletons from the Tambach Formation of Germany, which were fossilized lying next to each other.
Eonatator is an extinct genus of marine lizard belonging to the mosasaur family. It is a close relative of Halisaurus, and part of the same subfamily, the Halisaurinae. It is known from the Late Cretaceous of North America, Colombia and Sweden. Originally, this taxon was included within Halisaurus, but was placed in its own genus, which also led to the subfamily Halisaurinae being created for the two genera.
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.
Taniwhasaurus is an extinct genus of mosasaurs that lived during the Campanian stage of the Late Cretaceous. It is a member of the subfamily Tylosaurinae, a lineage of mosasaurs characterized by a long toothless conical rostrum. Two valid species are attached to the genus, T. oweni and T. antarcticus, known respectively from the fossil record of present-day New Zealand and Antarctica. Two other species have been nominally classified within the genus, T. 'capensis' and T. 'mikasaensis', recorded in present-day South Africa and Japan, but their attribution remains problematic due to the fragmentary state of their fossils. The generic name literally means "taniwha lizard", referring to a supernatural aquatic creature from Māori mythology.
Aerosaurus is an extinct genus within Varanopidae, a family of non-mammalian synapsids. It lived between 252-299 million years ago during the Early Permian in North America. The name comes from Latin aes (aeris) “copper” and Greek sauros “lizard,” for El Cobre Canyon in northern New Mexico, where the type fossil was found and the site of former copper mines. Aerosaurus was a small to medium-bodied carnivorous synapsid characterized by its recurved teeth, triangular lateral temporal fenestra, and extended teeth row. Two species are recognized: A. greenleeorum (1937) and A. wellesi (1981).
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 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.
The blue-tailed monitor, blue-tailed tree monitor or Kalabeck's monitor, is a monitor lizard of the Varanidae family. It belongs to the V. doreanus group of the subgenus Euprepiosaurus.
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 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 during the Eocene epoch. It is known from well-preserved fossils found in the Bridger and Green River Formations of Wyoming, United States. The type species S. ensidens was described in 1870 as the first fossil lizard known from North America. A second species, S.orsmaelensis, is recognised from remains found in Europe. It is a close relative of Varanus, the genus that includes monitor lizards.
Jesairosaurus is an extinct genus of early archosauromorph reptile known from the Illizi Province of Algeria. It is known from a single species, Jesairosaurus lehmani. Although a potential relative of the long-necked tanystropheids, this lightly-built reptile could instead be characterized by its relatively short neck as well as various skull features.
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 darevskii, also known as the Central Asian monitor, is an extinct species of monitor lizard from the Early Pliocene of Tajikistan, known from a partial skull. V. darevskii might have been a close relative of, and perhaps ancestral to, the modern desert monitor.
Varanus hooijeri is an extinct species of medium-sized monitor lizard found in Liang Bua on Flores and possibly also Sumba, dating to the Late Pleistocene and Holocene.