| 词条 | Oxygonioceras |
| 释义 |
| name = Oxygonioceras | fossil_range = M Silurian | image = | regnum = Animalia | phylum = Mollusca | classis = Cephalopoda | subclassis = Nautiloidea | ordo = Oncocerida | familia = Brevicoceratidae | genus = Oxygonioceras | genus_authority = }} Oxygonioceras is a genus in the Oncocerid family, Brevicoceratidae, from the Middle Silurian of North America and Europe. Oxygonioceras, named by Foeste, 1925, has a loosely coiled, dextrally torticonic shell with a rounded dorsum on the inside of the spiral and an angular or subangular venter on the outside; suture with broad lateral lobes and ventral siphuncle with expanded, nummuloidal segments. Although also torticonically gyroconic—having an out of plane open spiral - Oxygonioceras differs from Naedyceras and closely related genera in that the siphuncle segments are empty, rather than being actinosiphonate. See also
References
2 : Nautiloids|Paleozoic life of Manitoba |
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