| 词条 | Maelonoceras |
| 释义 |
| fossil_range = Ordovician - Silurian | image = | regnum = Animalia | phylum = Mollusca | classis = Cephalopoda | superordo = Nautilitoidea | ordo = Oncocerida | familia = | genus = Maelonoceras | genus_authority = Hyatt 1884 }} Maelonoceras is a Late Ordovician - early Silurian oncocerid found in Ontario. DescriptionThe shell is a faintly gibbous exogastric cyrtocone with subparallel dorsal and ventral profiles but adorally converging sides. The aperture vizored, pear-shaped. The Siphuncle small, ventral. Taxonomic relationMaelonoceras is nautiloid cephalopod included in the Oncoceratidae along with such genera as Oncoceras, Belotoceras, Digenuoceras, and Maimoceras. References{{no footnotes|date=October 2015}}
3 : Nautiloids|Late Ordovician first appearances|Silurian extinctions |
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