Ammonite - Harpoceras

myminifactory

Assemblage of pyritized ammonites, specifically Harpoceras falciferum, discovered in Dorset. This extinct genus of cephalopod belongs to the Hildoceratidae family and thrived during the Jurassic period, precisely within the Toarcian age from the Falciferum zone to the Commune subzone of Bifrons zone. As active predators, these fast-moving nektonic carnivores roamed the waters. The shells of Harpoceras species exhibit distinct dimorphism in size, with microconchs ranging from 24-51 mm in diameter and macroconchs reaching widths of 115-430 mm. These shells are moderately evolute to involute and compressed, featuring flat whorl sides and a strong keel. The ribs are falcoid or falcate, biconcave, strong, and projected, with some species displaying broad and flat-topped outer ribs and striated inner ribs. Certain species also showcase midlateral grooves or series of undulating depressions on the inner half of the whorl. This object was scanned using an Artec spider scanner and processed with Artec studio 12 by M Partridge.