Rare Fossil Heteromorph Uncoiled Ammonite (Anisoceras plicatile) – Lower Cenomanian, Upper Cretaceous, Adur Valley UK – Genuine + COA

Description

A rare heteromorph uncoiled ammonite (Anisoceras plicatile), from the Lower Cenomanian Stage of the Upper Cretaceous, collected at Adur Valley, United Kingdom. This specimen is highly collectable, displaying the distinctive irregular, partially uncoiled morphology characteristic of Anisoceras. The fossil pictured is the exact one you will receive, and it is supplied with a Certificate of Authenticity.

Fossil Type & Species:

• Type: Heteromorph Ammonite (extinct marine cephalopod)
• Species: Anisoceras plicatile
• Order: Ammonitida
• Superfamily: Turrilitoidea
• Family: Anisoceratidae

Geological Context:

• Period: Cretaceous
• Epoch/Stage: Upper Cretaceous – Lower Cenomanian (approx. 100.5 to 97 million years ago)
• Biozone: Typically associated with Mantelliceras mantelli Zone, an important ammonite horizon of the Lower Cenomanian
• Formation: Cenomanian chalk deposits (White Chalk Subgroup, southern England)
• Depositional Environment: Shallow marine chalk seas with calcareous sedimentation, excellent for fossil preservation

Locality:

• Region: Adur Valley, United Kingdom

Morphology & Features:

• Irregularly uncoiled and curved shell, often forming hook-like or spiral structures
• Strong ribbing and ornamentation extending across the flanks
• Unique heteromorph coiling distinguishes Anisoceras from other ammonite genera
• Excellent preservation with visible structural detail

Scientific Notes:

• Anisoceras plicatile was first described in 19th-century studies of British Cretaceous ammonites
• Its distinctive uncoiled form makes it an important index species for Lower Cenomanian ammonite biostratigraphy
• Represents evolutionary experimentation in heteromorph ammonite morphology during the Cretaceous

Notable Details:

• Rare British heteromorph ammonite from a classic Cretaceous chalk locality
• Excellent preservation with ribbing and unusual shell coiling clearly visible
• 100% genuine, natural fossil – no restoration
• Scale Reference: Each square or cube = 1cm. Please see photographs for accurate sizing

Authenticity & Guarantee: All of our fossils are 100% genuine, responsibly sourced, and professionally curated. Each specimen is supplied with a Certificate of Authenticity. The fossil pictured is the exact one you will receive.

This Anisoceras plicatile ammonite is a rare and scientifically important fossil from the Lower Cenomanian of the Adur Valley – an excellent addition for collectors, researchers, or natural history displays.