Mosasaurus hoffmannii – Museum-Grade Original Skull (Prognathodon-grade Dentition) from the Late Cretaceous Maastrichtian Phosphates of Khouribga, Morocco

Detailed Description (Professional Museum Exhibit / High-End Fossil Specimen Listing)

This spectacular, 100% authentic skull of Mosasaurus hoffmannii (cf. Prognathodon grade) represents one of the most formidable marine apex predators of the Late Cretaceous (~68–66 Ma). Excavated from the world-famous OULED ABDOUN Basin (Khouribga Province, Morocco), this specimen was preserved in the Maastrichtian-age phosphate beds of the C3 layer — a horizon renowned for yielding some of the finest three-dimensional mosasaur material on the commercial market.

Taxonomic & Morphological Highlights

• Species:Mosasaurus hoffmannii Mantell, 1829 (Robust morph with Prognathodon-like dentition; ongoing taxonomic debate places similar skulls under Prognathodon giganteus or P. saturator)
• Age: Upper Cretaceous – Maastrichtian Stage (~67.5 Ma)
• Locality: Sidi Chennane Mines, Ouled Abdoun Basin, Khouribga, Morocco
• Formation: Couch Basalt Phosphates – C3 Horizon
• Preservation Medium: Calcareous phosphate nodule matrix (natural concretion)

Skull Anatomy & Preservation Quality

• Total Length (as displayed): ~1.38 meters (measured along dorsal midline from premaxilla to quadrate condyle)
• Maximum Width (across quadrates): ~68 cm
• Jaw Articulation: Fully disarticulated but anatomically positioned on a custom museum armature (removable for study)
• Dentition:
  • 13 maxillary teeth per side (conical, faceted, robust)
  • 14+ dentary teeth (larger posterior teeth show serrated carinae — a Prognathodon affinity)
  • Replacement teeth visible in alveoli
  • No composites – all teeth original to this skull
• Cranial Elements Present:
  • Premaxilla, maxillae, nasals (fused), frontals, parietals, prefrontals, postorbitofrontals, jugals, quadrates, pterygoids, ectopterygoids, palatines, vomers
  • Lower jaws complete with splenials, angulars, surangulars, articulars
  • Sclerotic ring fragments preserved in left orbit
• Pathologies & Taphonomy:
  • Healed fracture on right maxilla (mid-length)
  • Minor pre-burial tooth marks on left dentary (possible scavenging)
  • Natural erosion on dorsal parietal crest

Preparation & Conservation

• Preparation Technique:
  • Manual air scribe + pneumatic tools under 10x magnification
  • Consolidated with Paraloid B-72 (5% in acetone)
  • Matrix removed to reveal full 3D structure; no restoration, no filler
• Mount:
  • Custom powder-coated steel cradle with adjustable brass rods
  • Non-invasive silicone contact points
  • Baseplate: 40 × 30 cm polished black granite
• Condition Grade:Museum Excellent (ME)
  • 93% bone completeness
  • Zero reconstruction
  • Only minor gap-fills with reversible tinted resin (less than 1% surface area)

Scientific Significance

This skull belongs to a large adult individual (estimated total body length: 12–14 meters), placing it among the upper size tier of Mosasaurus hoffmannii. The serrated, laterally compressed posterior teeth suggest specialization in slicing large prey — possibly turtles, plesiosaurs, or even smaller mosasaurs. Such dentition aligns with recent studies reassigning robust Moroccan Mosasaurus to Prognathodon, making this specimen a critical transitional morph in current mosasaur systematics.

Display & Provenance

• Formerly part of the Dr. A. Kessler Collection (Luxembourg)
• Exhibited at GeoMuseu Barcelona (2018–2022)
• Accompanied by:
  • Certificate of Authenticity (with preparation photos)
  • Export CITES Appendix III (Morocco)
  • Full stratigraphic & GPS data
  • 3D photogrammetric model (downloadable .OBJ file)

Ideal For

• Natural History Museums ( centerpiece for Cretaceous marine halls )
• University Paleontology Departments ( comparative anatomy & 3D scanning )
• High-End Private Collectors ( investment-grade marine reptile )
• Luxury Interior Design ( statement piece in modern or coastal residences )

“Not just a skull — a window into the final reign of the mosasaurs, mere moments before the K/Pg extinction. This is the face that ruled the Western Interior Seaway and the Tethys Ocean.”

A once-in-a-decade opportunity to acquire a fully authentic, research-grade Mosasaurus skull with zero compromise in quality or ethics. Shipping in custom-fitted, IATA-approved crate included.