Species Name: Phylloceras isotypum
Age: Jurassic, Callovian, 163 to 166 Mya.
Location: Bereketa, Madagascar.
Phylloceras isotypum ammonite fossil collected from the Jurassic, Callovian rocks of Bereketa, Madagascar which date back approximately 163 to 166 Mya. Phylloceras is an extinct genus of ammonite which exploited Early Jurassic through to Late Cretaceous seas. Typically they have smooth, involute shells, meaning the early whorls are not visible. The classic ammonitic suture is often visible in this species. These particular ammonites were deposited when a Callovian marine transgression resulted in the deposition of basinal mudstones in Beraketa; oxygen depleted conditions resulted in the fine preservation of abundant fauna including Phylloceras isotypum. These examples are approximately 2.5 cm in diameter and are supplied in small plastic bags with an information label.