''Lemmysuchus'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of machimosaurid

thalattosuchia Thalattosuchia is a clade of mostly marine crocodylomorphs from the Early Jurassic to the Early Cretaceous that had a cosmopolitan distribution. They are colloquially referred to as marine crocodiles or sea crocodiles, though they are not member ...

n from the

Middle Jurassic The Middle Jurassic is the second Epoch (geology), epoch of the Jurassic Period (geology), Period. It lasted from about 174.1 to 161.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relativel ...

Callovian In the geologic timescale, the Callovian is an age and stage in the Middle Jurassic, lasting between 165.3 ± 1.1 Ma (million years ago) and 161.5 ± 1.0 Ma. It is the last stage of the Middle Jurassic, following the Bathonian and preceding the ...

England England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It ...

and

France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...

. Like many other teleosauroids from Europe, it has had a convoluted taxonomic history.

History

''"Steneosaurus" obtusidens'' was first described from the

-aged

Oxford Clay Formation The Oxford Clay (or Oxford Clay Formation) is a Jurassic marine sedimentary rock formation underlying much of southeast England, from as far west as Dorset and as far north as Yorkshire. The Oxford Clay Formation dates to the Jurassic, specific ...

Cambridgeshire Cambridgeshire (abbreviated Cambs.) is a Ceremonial counties of England, ceremonial county in the East of England and East Anglia. It is bordered by Lincolnshire to the north, Norfolk to the north-east, Suffolk to the east, Essex and Hertfor ...

, southeastern England on the basis of a partial skeleton (NHMUK PV R 3168). Characters cited as diagnostic for ''"S." obtusidens'' included: short rostrum (preorbital length 52 percent of total skull length); teeth blunt and rounded at the tips; armor adorned with elongate pit ornamentation. The validity of ''"Steneosaurus" obtusidens'' was disputed in a 1987 paper reviewing the type specimens of nominal teleosauroid species from the Oxford Clay. Characters used by

Charles William Andrews Charles William Andrews (30 October 1866 – 25 May 1924) F.R.S., was a British palaeontologist whose career as a vertebrate paleontologist, both as a curator and in the field, was spent in the services of the British Museum, Department of Ge ...

to distinguish ''"S." obtusidens'' from other species were dismissed as variable within specimens of '' Steneosaurus edwardsi'', and ''"S." obtusidens'' was sunk as a junior synonym of ''Steneosaurus durobrivensis'' (=''S. edwardsi''). Some authors considered this taxon a probable junior synonym of '' Machimosaurus hughii'' based on a subsequently discovered specimen found in Callovian-age exposures in

Calvados Calvados (, , ) is a brandy from Normandy in France, made from apples and/or pears. History In France Apple orchards and brewers are mentioned as far back as the 8th century by Charlemagne. The first known record of Norman distillation was ma ...

Lower Normandy Lower Normandy (, ; ) is a former administrative region of France. On 1 January 2016, Lower and Upper Normandy merged becoming one region called Normandy. Geography The region included three departments, Calvados, Manche and Orne, that cover ...

, France, though they stressed that a taxonomic review of blunt-snouted teleosaurids was needed. This synonymy was accepted in a 2009 paper regarding thalattosuchian morphometrics without comment. In 2013, a new specimen of ''Machimosaurus'' was described from Late Jurassic (

Kimmeridgian In the geologic timescale, the Kimmeridgian is an age in the Late Jurassic Epoch and a stage in the Upper Jurassic Series. It spans the time between 154.8 ±0.8 Ma and 149.2 ±0.7 Ma (million years ago). The Kimmeridgian follows the Oxfordian ...

deposits in southern Germany (later named ''Machimosaurus buffetauti''), and it became clear that variation within blunt-toothed teleosauroids was taxonomically significant enough for ''"Steneosaurus" obtusidens'' to be recognized as generically distinct from ''Machimosaurus''. Other cladistic and comparative studies agreed with this assessment, recovering ''"S." obtusidens'' in a clade with ''Machimosaurus'' and ''Steneosaurus edwardsi''. In 2017, the species was moved to its own genus, ''Lemmysuchus'', referring to

Ian Fraser Kilmister Ian Fraser Kilmister (24 December 1945 – 28 December 2015), better known as Lemmy Kilmister or simply Lemmy, was a British musician. He was the founder, lead vocalist, bassist and primary songwriter of the metal band Motörhead, of which he ...

, better known as "Lemmy", of the band

Motörhead Motörhead () were an English rock music, rock band formed in London in 1975 by bassist and lead vocalist Lemmy Kilmister, guitarist Larry Wallis and drummer Lucas Fox. Kilmister was the primary songwriter and only constant member. The band a ...

, and the Greek word for crocodile, .

References

{{Taxonbar, from=Q18926257 Fossil taxa described in 2017 Middle Jurassic crocodylomorphs Middle Jurassic reptiles of Europe Fossils of France Fossils of Great Britain Prehistoric pseudosuchian genera