ENGLAND

SOMERSET COUNTY

DONIFORD BAY

BLUE LIAS FORMATION

CALOCERAS JOHNSTONI AMMONITE SUBZONE

PSILOCERASPLANORBISAMMONITE ZONE

HETTANGIAN STAGE

LOWER LIAS EPOCH

EARLY JURASSIC

EARLY JURASSIC

STEM: TETRAPODA GOODRICH, 1930

SUPERCLASS: AMNIOTA HAECKEL, 1866

CLASS: REPTILIA LAURENTI, 1768

SUBCLASS: DIAPSIDA OSBORN, 1904

INFRACLASS: NEODIAPSIDA BENTON, 1985

NEODIAPSIDA: INCERTAE SEDIS

OR AMNIOTA: INCERTAE SEDIS

MAGANORDER: ICHTHYOPTERYGIA BAUR, 1887 emend nova

SUPERORDER: EOICHTHYOSAURIA MOTANI, 1999

GRANDORDER: ICHTHYOSAURIA EMEND BLAINVILLE, 1835

MICRORDER: LONGIPINNATI HUENE, 1948

ORDER: MERRIAMOSAURIA MONTANI, 1999

SUBORDER: EUICHTHYOSAURIA MONTANI, 1999

INFRAORDER: PARVIPELVIA MONTANI, 1999

PARVORDER: NEOICHTHYOSAURIA SANDER, 2000

Superfamily: ICHTHYOSAUROIDEA Bonaparte, 1841 (Emend McGowan & Montani, 2003)

Family: ICHTHYOSAURIDAE Bonaparte, 1841

Ichthyosaurus somersetensis

_____________________________________________________________________________________

ENGLAND

SOMERSET COUNTY

STREET

LOWERMOST HETTANGIAN STAGE

LOWER LIAS EPOCH

EARLY JURASSIC

STEM: TETRAPODA GOODRICH, 1930

SUPERCLASS: AMNIOTA HAECKEL, 1866

CLASS: REPTILIA LAURENTI, 1768

SUBCLASS: DIAPSIDA OSBORN, 1904

INFRACLASS: EURYAPSIDA COLBERT, 1945

SUPERORDER: SAUROPTERYGIA OWEN 1860

GRANDORDER: EOSAUROPTERYGIA emend RIEPPEL, 1994

ORDER: PLESIOSAURIA OWEN, 1840 NON BLAINVILLE, 1835

SUBORDER: PLESIOSAURIA OWEN, 1840 NON BLAINVILLE, 1835

INFRAORDER: PLIOSAUROMORPHA NOVA

Superfamily: PLIOSAUROIDEA Seeley, 1874

Family: RHOMALEOSAURIDAE Nopsca, 1928

*Avalonnectes arturi

*Stratesaurus taylori

_____________________________________________________________________________________

SOUTHERN UNITED KINGDOM

ENGLAND

SOMERSET COUNTY

WATCHET

PRE-PLANORBIS BEDS

HETTANGIAN STAGE

LOWER LIAS EPOCH

EARLY JURASSIC

Note: Marine deposit.

STEM: TETRAPODA GOODRICH, 1930

SUPERCLASS: AMNIOTA HAECKEL, 1866

CLASS: REPTILIA LAURENTI, 1768

SUBCLASS: DIAPSIDA OSBORN, 1904

SUPERLEGION: NEODIAPSIDA BENTON, 1985

LEGION: ARCHOSAUROMORPHA HUENE, 1946

SUPERCOHORT: CRUROTARSI SERENO & ARCUCCI, 1990

COHORT: CROCODYLOTARSI BENTON & CLARK, 1988

SUPERORDER: PARASUCHIMORPHA NOVA

ORDER: PARASUCHIA HUXLEY, 1875

Family: MYSTRIOSUCHIDAE Huene, 1915

Subfamily: MYSTRIOSUCHINAE Huene, 1915 (sensu Chatterjee, 1978)

aff. Mystriosuchus sp

_____________________________________________________________________________________

SOUTHERN UNITED KINGDOM

ENGLAND

SOMERSET COUNTY

WATCHET

LOWERMOST HETTANGIAN STAGE

LOWER LIAS EPOCH

EARLY JURASSIC

STEM: TETRAPODA GOODRICH, 1930

SUPERCLASS: AMNIOTA HAECKEL, 1866

CLASS: REPTILIA LAURENTI, 1768

SUBCLASS: DIAPSIDA OSBORN, 1904

INFRACLASS: EURYAPSIDA COLBERT, 1945

SUPERORDER: SAUROPTERYGIA OWEN 1860

GRANDORDER: EOSAUROPTERYGIA emend RIEPPEL, 1994

ORDER: PLESIOSAURIA OWEN, 1840 NON BLAINVILLE, 1835

SUBORDER: PLESIOSAURIA OWEN, 1840 NON BLAINVILLE, 1835

INFRAORDER: PLIOSAUROMORPHA NOVA

Superfamily: PLIOSAUROIDEA Seeley, 1874

Incertae sedis

*Eoplesiosaurus antiquior

_____________________________________________________________________________________

ENGLAND

SOMERSET COUNTY

STREET

PSILOCERAS PLANORBIS ZONE

HETTANGIAN-PLIENSBACHIAN STAGE

LOWER LIAS EPOCH

EARLY EARLY JURASSIC

STEM: TETRAPODA GOODRICH, 1930

SUPERCLASS: AMNIOTA HAECKEL, 1866

CLASS: REPTILIA LAURENTI, 1768

SUBCLASS: DIAPSIDA OSBORN, 1904

INFRACLASS: EURYAPSIDA COLBERT, 1945

SUPERORDER: SAUROPTERYGIA OWEN 1860

GRANDORDER: EOSAUROPTERYGIA emend RIEPPEL, 1994

ORDER: PLESIOSAURIA OWEN, 1840 NON BLAINVILLE, 1835

SUBORDER: PLESIOSAURIA OWEN, 1840 NON BLAINVILLE, 1835

INFRAORDER: PLESIOSAUROMORPHA NOVA

EUPLESIOSAURIA O’KEEFE, 2001

Family: PLESIOSAURIDAE Gray, 1825

Thalassiodracon hawkinsii
= Plesiosaurus hawkinsii

_____________________________________________________________________________________