Meyerasaurus
Encyclopedia
Meyerasaurus is an extinct genus
of rhomaleosaurid known from Holzmaden
, Baden-Württemberg
of southeastern Germany
.
SMNS 12478, articulate
d and complete skeleton
which preserved the skull
, exposed in ventral view. The skull has a length of 37 cm (14.6 in), and the animal is about 3.35 m (11 ft) in length. It was collected from the Harpoceras elegantulum-falciferum ammonoid subzones, Harpoceras falcifer zone, of the famous Posidonien-Schiefer lagerstätte
(Posidonia Shale
), dating to the early Toarcian
stage of the Early Jurassic
, about 183-180 million years ago.
and the type species
is Meyerasaurus victor. It was originally classified as a species of Plesiosaurus
, later as the second named species of Thaumatosaurus (defunct name, meaning "wonder reptile") and ultimately as a species of Eurycleidus
or Rhomaleosaurus
. The generic name honors the German palaeontologist Hermann von Meyer for proposing the generic name Thaumatosaurus.
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 rhomaleosaurid known from Holzmaden
Holzmaden
Holzmaden is a town in Baden-Württemberg, Germany that lies between Stuttgart and Ulm.The ground in and around the city contains rich layers of well preserved fossils of the Jurassic period. The fossils are found in the 160 million year old Posidonia Shale and displayed in the local Museum Hauff...
, Baden-Württemberg
Württemberg
Württemberg , formerly known as Wirtemberg or Wurtemberg, is an area and a former state in southwestern Germany, including parts of the regions Swabia and Franconia....
of southeastern Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
.
Description
Meyerasaurus is known from the holotypeHolotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
SMNS 12478, articulate
Articulate
Articulate may refer to:*Articulate *Articulate sign*Articulate sound*Joint, also known as articulation*Word modified by an article...
d and complete skeleton
Skeleton
The skeleton is the body part that forms the supporting structure of an organism. There are two different skeletal types: the exoskeleton, which is the stable outer shell of an organism, and the endoskeleton, which forms the support structure inside the body.In a figurative sense, skeleton can...
which preserved the skull
Skull
The skull is a bony structure in the head of many animals that supports the structures of the face and forms a cavity for the brain.The skull is composed of two parts: the cranium and the mandible. A skull without a mandible is only a cranium. Animals that have skulls are called craniates...
, exposed in ventral view. The skull has a length of 37 cm (14.6 in), and the animal is about 3.35 m (11 ft) in length. It was collected from the Harpoceras elegantulum-falciferum ammonoid subzones, Harpoceras falcifer zone, of the famous Posidonien-Schiefer lagerstätte
Lagerstätte
A Lagerstätte is a sedimentary deposit that exhibits extraordinary fossil richness or completeness.Palaeontologists distinguish two kinds....
(Posidonia Shale
Posidonia Shale
The Posidonia Shale is a Lower Jurassic geological formation famous for its exceptionally well-preserved complete skeletons of fossil marine fish and reptiles. The Posidonienschiefer as German paleontologists call it, takes its name from the ubiquitous fossils of Posidonia bronni that characterize...
), dating to the early Toarcian
Toarcian
The Toarcian is, in the ICS' geologic timescale, an age or stage in the Early or Lower Jurassic. It spans the time between 183.0 Ma and 175.6 Ma...
stage of the Early Jurassic
Early Jurassic
The Early Jurassic epoch is the earliest of three epochs of the Jurassic period...
, about 183-180 million years ago.
Etymology
Meyerasaurus was first named by Adam S. Smith and Peggy Vincent in 20102010 in paleontology
-Anomalocaridids:-Newly named crustaceans:-Newly named insects:* A new family, Cascopleciidae, is published by Poinar Jr.* A new family of ceraphronoid Hymenopters, Radiophronidae, is published by Ortega-Blanco, Rasnitsyn, and Delclòs....
and the type species
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...
is Meyerasaurus victor. It was originally classified as a species of Plesiosaurus
Plesiosaurus
Plesiosaurus was a genus of large marine sauropterygian reptile that lived during the early part of the Jurassic Period, and is known by nearly complete skeletons from the Lias of England...
, later as the second named species of Thaumatosaurus (defunct name, meaning "wonder reptile") and ultimately as a species of Eurycleidus
Eurycleidus
Eurycleidus is an extinct genus of plesiosaur. The type species is E. arcuatus, which lived during the Hettangian age . Like other plesiosaurs, Eurycleidus probably lived on a diet of fish, using its sharp needle-like teeth to catch prey. Its shoulder bones were fairly large, indicating a powerful...
or Rhomaleosaurus
Rhomaleosaurus
Rhomaleosaurus is an extinct genus of Early Jurassic rhomaleosaurid pliosauroid known from Northamptonshire and from Yorkshire of the United Kingdom. It was first named by Harry Seeley in 1874 and the type species is Rhomaleosaurus cramptoni...
. The generic name honors the German palaeontologist Hermann von Meyer for proposing the generic name Thaumatosaurus.