Cherminotus
Encyclopedia
Cherminotus is an extinct genus
of monitor lizard
from the Late Cretaceous
of Mongolia
. The type
and only species, C. longifrons, was named in 1984.
. More specimens were later found in the Djadokhta Formation in localities such as Ukhaa Tolgod.
Cherminotus is small for a monitor lizard and has a longer snout than its closest relative, the living Earless monitor lizard. Cherminotus is also very similar in appearance to Aiolosaurus
, another monitor from the Cretaceous of Mongolia. Both monitors have a single hole in the lacrimal bone
called the lacrimal foramen. Other monitors and monitor ancestors have two holes in the lacrimal, making the presence of only one hole in Cherminotus a case of evolutionary reversal.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of monitor lizard
Monitor lizard
Monitor lizards are usually large reptiles, although some can be as small as in length. They have long necks, powerful tails and claws, and well-developed limbs. Most species are terrestrial, but arboreal and semiaquatic monitors are also known...
from the Late Cretaceous
Late Cretaceous
The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...
of Mongolia
Mongolia
Mongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest...
. The type
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
and only species, C. longifrons, was named in 1984.
Description and history
Cherminotus longifrons was first described in 1984 from the Barun Goyot FormationBarun Goyot Formation
The Barun Goyot Formation , dating from the Late Cretaceous Period, is located within and is widely represented in the Gobi Desert basin, in the Ömnögovi Province of Mongolia....
. More specimens were later found in the Djadokhta Formation in localities such as Ukhaa Tolgod.
Cherminotus is small for a monitor lizard and has a longer snout than its closest relative, the living Earless monitor lizard. Cherminotus is also very similar in appearance to Aiolosaurus
Aiolosaurus
Aiolosaurus is an extinct genus of monitor lizard from the Late Cretaceous of Mongolia. The type and only species, A. oriens, was named in 2000 from Ukhaa Tolgod, a rich fossil site in the Campanian-age Djadochta Formation.-Description and history:...
, another monitor from the Cretaceous of Mongolia. Both monitors have a single hole in the lacrimal bone
Lacrimal bone
The lacrimal bone, the smallest and most fragile bone of the face, is situated at the front part of the medial wall of the orbit. It has two surfaces and four borders.-Lateral or orbital surface:...
called the lacrimal foramen. Other monitors and monitor ancestors have two holes in the lacrimal, making the presence of only one hole in Cherminotus a case of evolutionary reversal.