-
Ellesmerocerida and
renamed it
Clarkoceras newton-winc****i (Clarke),
which became the genotype. The
earliest known Clarkoceras comes from the
upper Trempealeauan...
-
other Late
Cambrian ellesmeroceratid genera,
except for
Ectenolites and
Clarkoceras,
which persisted into the Ordovician. Late
Cambrian Tanycamerocers (Ellesmeroceratidae)...
-
crossed (barely) into the Ordovician, with two genera,
Ectenolites and
Clarkoceras.
Ordovician ellesmerocerids in turn
likely gave rise to
several new nautiloid...
-
restricted to the Wan****ou,
except for
Clarkoceras and Ectenolites,
which persist into the
Lower Ordovician.
Clarkoceras and
Ectenolites provide the ancestry...
- Ellesmeroceratidae,
continued by
means of the
genera Ectenolites and
Clarkoceras into the
Gasconadian in the
Lower Ordovician. The
other three, Acaroceratidae...
- †Cincinnetina †Cincinnetina
multisecta †Cladochonus †Clarkeipterus †
Clarkoceras †Climacograptus †****endoceras †Clorinda †Coenites †Columnaria †Conocardium...
- †Chouteauoceras †Chrysoceras †Chuticeras †Cimonia †Cinctoceras †Clarkesvillia †
Clarkoceras †Clathroceras †Clelandoceras †Cliftonoceras †Clinoceras †Clionyssiceras...
-
testudineus – type
locality for
species †
Clarkoceras †
Clarkoceras rhomboidale †
Clarkoceras ruedemanni †
Clarkoceras trapezoidale †Clathrodictyon †Clathropora...
- Ellesmerocerida, and
predominantly to the Ellesmeroceratidae.
Among these were
Clarkoceras and
Ectenolites which continued from the Late Cambrian,
along with the...
- †Chonetes †Chonetes
geniculatus †Chonetes
mesoloba †Chonetes
ornatus †
Clarkoceras †Cleiothyridina †Cleiothyridina incr****ata †Cleiothyridina orbicularis...
