| 词条 | Paratornoceratinae |
| 释义 |
| fossil_range = Devonian | image = | image_caption = | taxon = Paratornoceratinae | authority = Ebbighausen, Becker, & Bockwinkel, 2002 | subdivision_ranks = Genera | subdivision =
}} Paratornoceratinae is a subfamily of oxyconic dimeroceratids included in the order Goniatitida, a group of Paleozoic ammonoids, which have closer affinity to living coleoids than to Nautilus. Paratornoceratinae as defined by Ebbighausen, Becker, & Bockwinkel in 2002 comprises three recognised genera with sharp, oxyconic, venters; Acrimeroceras, Paratornoceras, and Polonites. The shell, as described for the type, Paratornoceras, is subglobular and evolute on young stages, but discoidal and with closed umbilicus in the adult. References
3 : Dimeroceratidae|Devonian first appearances|Devonian extinctions |
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