- hypothetical.
Polydesmia was once
thought to be the
ancestral form of the
actinocerids, and was
derived from the
ellesmeroceriid Bathmoceras. However, it turned...
-
million years ago
during the Carboniferous.
Although they
resemble earlier actinocerids they are now
thought to
belong to the
Pseudorthocerida Rayonnoceras is...
-
nautiloid cephalopods, is
prevalent among the ellesmerocerids, endocerids,
actinocerids, orthoceratoids, and bactritids.
Orthocones existed from the Late Cambrian...
-
Calhounoceras is a
genus of
actinocerids (Cephalopoda, Nautiloidea) from the
Lower Mississippian named by Troedsson, 1926. Calhounoceras,
Fossilworks PaleoDB...
- ray Gr**** ἀκτίς, ἀκτῖνος (aktís, aktînos) actinic, actinism, actinium,
actinocerid, actinodrome, actinoid, actinomere, actinometer, actinomorphic, actinomyces...
-
problems with the
actinocerid hypothesis.
Carbactinocerids such as
Carbactinoceras appear much
later than the last
definite actinocerids,
leaving a large...
-
endosiphuncular deposits penetrated by a
canal system similar to that
found in
actinocerids but
differs in the
having a
protoconch characteristic of the pseudorthocerids...
-
early actinocerids defined by
Shimazu and
Obata in 1938 for
actinocerids with
thick connecting rings and a
complex irregular canal system.
Actinocerids are...
-
Lambeoceras is a
genus of
large actinocerids with a
convexly lenticular cross section from the
Upper Ordovician of
North America and the sole representative...
- New
Mexico with
features resembling those found in
actinocerids.
Pseudorthocerids and
actinocerids (respectively
Pseuorthocerida and Actinocerida) are...
