| 词条 | Placenticeras meeki |
| 释义 |
|name = Placenticeras meeki | image = Placenticeratidae - Placenticeras meeki.JPG | image_width = 250px | image_caption = Fossil shell of Placenticeras meeki on display at the Museo Civico di Storia Naturale di Milano | fossil_range = Late Cretaceous | regnum = Animalia | phylum = Mollusca | classis = Cephalopoda | subclassis = Ammonoidea | ordo= Ammonitida | superfamilia = Hoplitoidea | familia= Placenticeratidae | genus = Placenticeras | species = P. meeki | binomial = Placenticeras meeki | binomial_authority = (Böhm, 1898) | synonyms = }} Placenticeras meeki is an ammonite species from the Late Cretaceous. These cephalopods were fast-moving nektonic carnivores. They mainly lived in the American Interior Basin (Western Interior Seaway). DescriptionShells of this species could reach a diameter of about {{convert|1|m}}. They are discoidal, involute and compressed. Whorls are stout and rounded to diameter of 3 millimeters. The surface of fossils is usually covered by opalized nacre (ammolite). EtymologyThe name honours Fielding Bradford Meek. References
2 : Placenticeratidae|Late Cretaceous ammonites |
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