Ophisaurus

Superregnum: Eukaryota
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Superphylum: Deuterostomia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Megaclassis: Osteichthyes
Superclassis: Sarcopterygii
Superclassis: Tetrapoda
Cladus: Reptiliomorpha
Cladus: Amniota
Classis: Reptilia
Cladus: Eureptilia
Cladus: Romeriida
Subclassis: Diapsida
Cladus: Sauria
Infraclassis: Lepidosauromorpha
Superordo: Lepidosauria
Ordo: Squamata
Cladus: Unidentata, Episquamata, Toxicofera
Subordo: Anguimorpha
Infraordo: Neoanguimorpha
Superfamilia: Diploglossa

Familia: Anguidae
Subfamilia: Anguinae
Genus: Ophisaurus
Species (6): O. attenuatus – O. ceroni – O. compressus – O. incomptus – O. mimicus – O. ventralis
Name

Ophisaurus Daudin, 1803: 188

Type species: Anguis ventralis Linnaeus, 1766, by monotypy.

References
Primary references

Daudin, F.M. 1803. Division des Ophidiens en vingt-trois genres. Bulletin des Sciences, par la Société Philomatique 3(72): 187–188. BHL

Additional references

Lavin, B.R. & Girman, D.J. 2019. Phylogenetic relationships and divergence dating in the Glass Lizards (Anguinae). Molecular Phylogenetics and Evolution 133: 128–140. DOI: 10.1016/j.ympev.2018.12.022 Paywall Reference page.

Vernacular names
English: North American Glass Lizards

Ophisaurus (from the Greek 'snake-lizard') is a genus of superficially snake-like lizards in the family Anguidae. Although most species have no legs, their head shapes, movable eyelids, and external ear openings identify them as lizards. A few species have very small, stub-like legs near their rear vents. These are vestigial organs, meaning they once served an evolved purpose but are no longer used. They reach lengths of up to 1.2 metres (4 ft), but about two-thirds of this is the tail. Glass lizards feed on insects, spiders, other small reptiles, and young rodents. Their diets are limited by their inability to unhinge their jaws. Some glass lizards give birth to live young but most lay eggs.

They are so-named because their tails are easily broken; like many lizards, they have the ability to deter predation by dropping off part of the tail, which can break into several pieces, like glass. The tail remains mobile, distracting the predator, while the lizard becomes motionless, allowing eventual escape. This serious loss of body mass requires a considerable effort to replace, and can take years to do so. Despite this ability, the new tail is usually smaller than the original.

Feeding

Their diets consist primarily of arthropods, with larger animals eating snails and small mammals.
Species

The genus Ophisaurus (sensu lato) contains two monophyletic sister clades, one native to North America, the other to Asia, the latter is sometimes treated as the separate genus Dopasia.[2][3]

Nota bene: A binomial authority in parentheses indicates that the species was originally described in a genus other than Ophisaurus.

Ophisaurus sensu stricto: (native to North America)
Ophisaurus attenuatus Baird, 1880 – slender glass lizard
Ophisaurus ceroni Holman, 1965 – Ceron's glass lizard
Ophisaurus compressus Cope, 1900 – island glass lizard
Ophisaurus incomptus McConkey, 1955 – plainneck glass lizard
Ophisaurus mimicus Palmer, 1987 – mimic glass lizard
Ophisaurus ventralis (Linnaeus, 1766) – eastern glass lizard
Dopasia (native to Asia)
Dopasia buettikoferi (Lidth De Jeude, 1905) – Buettikofer's glass lizard
Dopasia gracilis (Gray, 1845) – Burmese glass lizard, Asian glass lizard, Indian glass snake
Dopasia hainanensis (Yang, 1984) – Hainan glass lizard
Dopasia harti (Boulenger, 1899) – Hart's glass lizard
Dopasia ludovici (Mocquard, 1905) – Ludovic's glass lizard
Dopasia sokolovi (Darevsky & Nguyen, 1983) – Sokolov's glass lizard
Dopasia wegneri (Mertens, 1959) – Wegner's glass lizard

Hyalosaurus from North Africa has also been included within the concept of Ophisaurus sensu lato, but genetic evidence has shown them to be more closely related to Anguis and Pseudopus.[3]
Fossil record

Ophisaurus sensu lato was once widely distributed in Europe, first appearing there during the Eocene, with its distribution at its maximum extent during the Miocene, their range had contracted to the Mediterranean by the late Pliocene. The youngest records of Ophisaurus in Europe are from southern Spain, dating to the Early-Mid Pleistocene transition around 800,000 years ago. The decline was likely caused by decreasing temperatures and increasing aridity due to the onset of glaciation.[4] Ophisaurus sensu lato likely dispersed into Asia from Europe before dispersing from Asia into North America via Beringia. The oldest records of Ophisaurus in North America are from the late Miocene.[5]
See also

American legless lizard
Pygopodidae
Slowworm
Limbless vertebrates

References

"Ophisaurus". Integrated Taxonomic Information System. www.itis.gov.
"Ophisaurus ", "Dopasia ", "Hyalosaurus ", "Pseudopus ". The Reptile Database. www.reptile-database.org.
Lavin, Brian R.; Girman, Derek J. (April 2019). "Phylogenetic relationships and divergence dating in the Glass Lizards (Anguinae)". Molecular Phylogenetics and Evolution. 133: 128–140. doi:10.1016/j.ympev.2018.12.022. hdl:10211.3/198486. PMID 30584918. S2CID 58560490.
Blain, Hugues-Alexandre; Bailon, Salvador (April 2019). "Extirpation of Ophisaurus (Anguimorpha, Anguidae) in Western Europe in the context of the disappearance of subtropical ecosystems at the Early-Middle Pleistocene transition". Palaeogeography, Palaeoclimatology, Palaeoecology. 520: 96–113. Bibcode:2019PPP...520...96B. doi:10.1016/j.palaeo.2019.01.023. S2CID 135280617.

Klembara, Jozef; Rummel, Michael (January 2018). "New material of Ophisaurus , Anguis and Pseudopus (Squamata, Anguidae, Anguinae) from the Miocene of the Czech Republic and Germany and systematic revision and palaeobiogeography of the Cenozoic Anguinae". Geological Magazine. 155 (1): 20–44. Bibcode:2018GeoM..155...20K. doi:10.1017/S0016756816000753. S2CID 132414700.