Protetragonites

Protetragonites is an extinct genus of ammonoid cephalopods belonging to the family Lytoceratidae. These fast-moving nektonic carnivores ^[1] lived from the Jurassic period Tithonian age to the Cretaceous period Aptian age.^[2]

Protetragonites Temporal range: from Jurassic to Cretaceous, 150.8–94.3 Ma PreꞒ Ꞓ O S D C P T J K Pg N [1]
Fossil shells of Protetragonites obliquestrangulatum from Alpes-de-Haute-Provence, on display at Galerie de paléontologie et d'anatomie comparée in Paris
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Subclass:	†Ammonoidea
Order:	†Ammonitida
Family:	†Lytoceratidae
Subfamily:	†Lytoceratinae
Genus:	†Protetragonites Hyatt, 1900
Synonyms
Hemitetragonites Spath, 1927 Leptotetragonites Spath, 1927

Species

^[1]

• Protetragonites crebrisulcatus Uhlig, 1883
• Protetragonites obliquestrangulatum (Kilian, 1889)
• Protetragonites quadrisulcatus d'Orbigny, 1841
• Protetragonites zuegeli Maisch & Salfinger-Maisch, 2016^[3]

Description

Shells of Protetragonites species reach a diameter of about 50 millimetres (2.0 in). Shells show few constrictions and a circular or triangular section.^[4]

Distribution

Fossils of species within this genus have been found in the Cretaceous rocks of Austria, Canada, Czech Republic, Slovakia, Dominican Republic, France, Hungary, Madagascar, Morocco, Poland, Spain, Russia, Ukraine, Western Sahara, as well in the Jurassic of Germany, Hungary and Italy.^[1]