-
include gyrocones, serpenticones, torticones, and
elongate orthocones and
cyrtocones,
reflective of the
different families and
genera (Flower, 1950; Sweet...
-
Upper Ordovician belonging to the Oncocerida,
characterized by
exogastric cyrtocones that
expand slightly or
moderately and have thin walled, orthochoanitic...
-
characterized by depressed, or
rarely compressed,
exogastric brevicones and
cyrtocones. The
Paleobiology Database Akt****cheilus
entry accessed 8/21/12 Sepkoski...
-
Oncocerida to
include genera characterized by
longiconic orthocones and
cyrtocones with a
subtriangular to
depressed cross-section in
which the
ventral (siphuncular)...
-
generally characteristic of its family, the Paraphragmitidae, an
annulated cyrtocone. In the case of
Calocyrtoceras striated both
transversely and longitudinally...
- of the
order Oncocerida,
Fayettoceras has a s****
which is a
depressed cyrtocone with a
ventral cyrtochoanitic siphuncle of
elongated ovoid segments strongly...
- conch, of
Cyrtocycloceras is a
moderately expanding annulated exogastric cyrtocone, with
curvature like that of a
rocking chair rocker. Annulations, encircling...
-
characterized by
depressed (or
rarely compressed)
exogastric brevicones and
cyrtocones (Sweet, 1964 K398) that
range from the
Middle Silurian to the
Middle Devonian...
-
Mingan Island. The s**** of
Minganoceras is a
slender depressed exogastric cyrtocone,
curved so that the underside, the venter, is
longitudinally convex and...
- of this
genus are
generally slender,
gradually expanding,
exograstric cyrtocones with an
ovoid cross section more
narrowly rounded ventrally than dorsally...
