- the Late Jur****ic,
coiled so that all
whorls are exposed.
Ribbing is
biplicate, with very
short secondaries. The venter, the
outer rim, is smooth, at...
- is evolute,
strongly and
sharply ribbed.
Ribbing is both
simple and
biplicate, with
primary ribs
bifurcating (splitting) on
either flank before crossing...
- within. The
peristome is
simple and very thin. The
columella is white,
biplicate and not prominent. This
species is
endemic to the
Wailuku Valley, West...
- sediments.
Aspidoceratinae differ from
Peltoceratinae in that the
early biplicate ribbed stage is lacking, or
greatly reduced, and no
forms with lappets...
-
dwarf ammonite.
Inner whorls smooth, spheroidal;
outer whorls with fine
biplicate ribbing,
ventral groove, and an
acute elbow at half a
whorl before the...
- The s**** has a
fusiform shape. The
sinus is
scarcely apparent. The
biplicate columella is
nearly straight. The
canal is
rather short and
slightly curved...
-
columella is
transversely oblique with a t****eled margin. It
terminates in a
biplicate tooth. The
inner lip
shows fine
linear elevations, with the last lira...
- They have a s****
morphology that is
mostly evolute,
typically with
biplicate, simple, or
triplicate ribbing.
Large forms have
simple apertures and...
- umbilicus,
bearing a
strong dentiform fold
above and a
large quadrangular biplicate tooth at the base. The
parietal wall is wrinkled. The
white umbilicus...
-
members of the
family Pyramidellidae. They may, however, have
slight biplicate folds on the columella.
Species in the
genus Tiberia include: Tiberia...
