-
which according to the
Treatise L, 1957,
evolved into
strongly ribbed planulates (discoidal
evolute s****) with
quadrate whorls,
typically with crenulated...
-
Stephanoceratidae is a
family of
planulate and
coronate ammonites within the Stephanoceratoidea. S**** are
evolute so that all
whorls are
exposed and...
- umbilici—cadiconic—but
become compressed, with the out rims
becoming bluntly rounded—
planulate.
Ribbing is common; may be
heavy and
tuberculate on the
umbilical shoulders...
-
Megalytoceratinae is a
subfamily of
lytoceratids ammonites consisting of
planulate forms, i.e.
those with
moderately evolute compressed s**** with bluntly...
- Hildoceratoidea,
formerly Hildoceratacaea, is a
superfamily of
compressed or
planulate ammonites, some
tending to
develop acute outer rims;
generally with arcuate...
- with one exception, as
genus Badouxia had weak
ventral chevron. S**** is
planulate, or serpenticone.
Sutures were
often asymmetrical and in some genera,...
- planation, plane, planification, planiform, planish, planula, planular,
planulate plang-, planct- strike, beat; lament,
mourn Latin plangere,
planctus plangent...
-
transiens Frentzen, 1937
Pleuroceras apyrenum Buckman, 1911
Pleuroceras has a
planulate s**** with a
quadrate whorl section,
bearing strong radial ribs ending...
- planation, plane, planification, planiform, planish, planula, planular,
planulate plang-, planct- strike, beat; lament,
mourn Latin plangere,
planctus plangent...
-
characterized by s**** that
begin as barrel-shaped
cadicones but
which become planulate later in life. Body
chambers are
reduced in size and are excentric. Similar...
