Solenoceras reesidei Stephenson 1941 from: Ifrim, C..Stinnesbeck, W..López-Oliva, J.G.. (2004): Maastrichtian cephalopods from Cerralvo, north-eastern Mexico . Palaeontology Vol. 47(6) p. 1575–1627 | . |
Notice: This catalogue page may contain unedited data.
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Species Solenoceras reesidei Stephenson 1941 |
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[1] Text-fig. 15a-e Ifrim et al. (2004)
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| Diagnosis / Definition: |
Ifrim et al. (2004):
Description: U-shaped and straight shell fragments with low to intermediate expansion rates. Cross section of the test
is oval. The cross section of the juvenile limb is rounded to compressed with ventrolateral shoulders and a narrow bow
towards the dorsum. The dorsum of the more adult limb is concavely grooved and contains the juvenile shaft with
rounded to triangular cross section. The test is ornamented with prominent simple ribs, with a rib index of c. 7. They
are straight and retracted towards the venter. Faint pairs of tubercles are present on the venter of two specimens. The
suture line is visible in part and very simple. |
| Discussion / Comments: |
Ifrim et al. (2004):
Remarks: Ribs are more densely arranged than in S. texanum (Shumard, 1861), and the cross section ofthe
smaller limb is more circular. The shell expands at a slightly faster rate which leads to astronger difference
in diameter between the juvenile and adult limb at comparable distances from the hook. Solenoceras
annulifer (Morton, 1841) and S. multicostatum (Stephenson, 1941) have finer ornament and depressed
reniform sections up to the adult shaft.ln comparison to S. multicostatum (Stephenson, 1941) both limbs of
S. reesidei are pressed onto each other more narrowly.
Occurrence: Solenoceras reesidei Stephenson is restricted to the northern Gulf of Mexico area and the Interior Seaway
of the USoIt was recorded from the Upper Campanian Baculites compressus and Baculites reesidei zones of the Pierre
Shale, Colorado (Cobban et al. 1992), the Upper Campanian Coon Creek Tongue of the Ripley Formation in
Tennessee (Cobban and Kennedy 1993a), and the Navarro Formation of Texas (Stephenson 1941; Cobban and
Kennedy 1991a). Solenoceras sp. was recorded from the Potrerillos Formation (Difunta Group, north-eastern Mexico)
and the Cardenas Formation (east-central Mexico), but specimens were not figured or described (Vega et al. 1995). |
| Systematics: |
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Ordo Ammonoidea
Subordo Ancyloceratina
Superfamilia Turrilitaceae
Familia Diplomoceratidae
Subfamilia Polyptychoceratinae
Genus Solenoceras
Species Solenoceras reesidei
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| Synonym list: |
Ifrim et al. (2004):
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| Stratigraphy - relative ages: |
upper Campanian: Ifrim et al. (2004)
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| References: |
Stephenson,L.W.. (1941):
The larger invertebrates of the Navarro Group of Texas (exclusive of corals and crustaceans and exclusive of the fauna of the Escondido Formation) . University of Texas, Bulletin Vol. 4101 p. 641 pp
Cobban,W.A..; Kennedy,W.J.. and SCOTT,G.R.. (1992):
Upper Cretaceous ammonites from the Baculites compressus Zone of the Pierre Shale in north-central Colorado. . United States Geological Survey, Bulletin Vol. 2024 p. A1-A11
Cobban,W.A.. and Kennedy,W.J.. (1993):
Upper Cretaceous ammonites from the Coon Creek Tongue of the Ripley Formation at its type locality in McNairy County, Tennessee . United States Geological Survey, Bulletin Vol. 2073 p. B1-B12
Ifrim,C..; Stinnesbeck,W.. and López-Oliva,J.G.. (2004):
Maastrichtian cephalopods from Cerralvo, north-eastern Mexico . Palaeontology Vol. 47(6) p. 1575–1627
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