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is a moderately expanding annulated exogastric cyrtocone, with curvature like that of a rocking chair rocker. Annulations, encircling ribs, are close spaced and transverse and the surface is transversely striated.
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Walter C. Sweet, 1964. Nautiloidea- Orthocerida. Treatise on
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from the Middle
Silurian of both Europe and North America is striated both transversely and longitudinally while
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is striated only longitudinally. Moreover the annulations on
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from the Middle
Silurian of Europe included in the
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176:tend to be thicker and further apart than on
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358:Prehistoric nautiloid genera
311:. You can help Knowledge by
368:Prehistoric nautiloid stubs
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36:Scientific classification
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149:The shell, or conch, of
26:Temporal range: Middle
307:-related article is a
270:Paleobiology Database
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303:This prehistoric
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257:Open Tree of Life
199:Taxon identifiers
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363:Silurian animals
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107:Paraphragmitidae
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178:Cyrtocycloceras
174:Gaspocyrtoceras
165:Gaspocyrtoceras
151:Cyrtocycloceras
135:Cyrtocycloceras
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120:Cyrtocycloceras
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138:is a genus of
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140:orthocerids
95:Orthocerida
83:Nautiloidea
71:Cephalopoda
352:Categories
184:References
78:Subclass:
305:nautiloid
222:Q22286719
42:Kingdom:
216:Wikidata
102:Family:
59:Mollusca
54:Phylum:
47:Animalia
28:Silurian
262:4154430
249:1157355
236:4621001
114:Genus:
90:Order:
66:Class:
275:127794
244:IRMNG
309:stub
231:GBIF
172:and
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340:e
333:t
326:v
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