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Notice: This catalogue page may contain unedited data.
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Subspecies Nostoceras (Nostoceras) n. sp. |
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Alternative name: |
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Diagnosis / Definition: |
Ward & Kennedy (1993):
Description. -
UWBM6 17 1 is composite mold of four successive
whorls with maximum preserved whorl height of 7.5
mm. Translation rate high, producing spire with very narrow
apical angle, whorls in contact throughout. Feeble to obsolete
low, broad, prorsiradiate ribs arise at upper whorl suture, and
sweep across upper half of exposed whorl face to coarse flattopped
tubercles situated in middle of exposed whorl face. Weak
ribs connect these to row of smaller, spirally elongated tubercles
at juncture of outer and lower whorl faces, and displaced adaperturally
of upper row. There appear to be more tubercles per
whorl in this row that in upper one. |
Discussion / Comments: |
Ward & Kennedy (1993):
Discussion.-
The coarse tuberculation distinguishes this specimen
from all others described from the European Maastrichtian.
It most closely resembles an as yet undescribed species
from the Prairie Bluff Chalk (Maastrichtian) of Alabama.
Occurrence.-
The single specimen was recovered from near
the top of Member I (lower Maastrichtian), at Sopelana 11. |
Systematics: |
38 Ordo Ammonoidea
Subordo Ancyloceratina
Superfamilia Turrilitaceae
Familia Nostoceratidae
Genus Nostoceras
Subspecies Nostoceras (Nostoceras) n. sp.
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Synonym list: |
Ward & Kennedy (1993):
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Stratigraphy - relative ages: |
lower Maastrichtian: Ward & Kennedy (1993)
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References: |
Ward,P.D.. and Kennedy,W.J.. (1993): Maastrichtian Ammonites from the Biscay Region (France, Spain) . Memoir (The Paleontological Society), Journal of Paleontology34 (Supplement to Vol. 67)(5) p. 1-58
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