Mosasaur Humerus
cf. Prognathodon currii or cf. Mosasaurus beaugei • Body fossil - Vertebrate (Marine Reptile)
Geological Period
Late Cretaceous (Maastrichtian)
Estimated Age
66 to 72 million years
Preservation Type
Permineralization with some phosphate replacement and heavy mineralization typical of the Ouled Abdoun Basin deposits.
Condition Assessment
Fair to Good. The specimen shows significant repair with visible adhesive lines/bonding through the mid-shaft and some surface erosion. It is relatively complete in its general outline but lacks fine anatomical detail at the joint surfaces.
Taxonomic Classification
Phylum: Chordata, Class: Reptilia, Order: Squamata, Family: Mosasauridae, Genus: Prognathodon or Mosasaurus
Morphological Description
Robust, flattened limb bone exhibiting a distinctively flared distal end (for articulation with radius/ulna) and a thickened proximal head. The shaft is short and constricted, typical of aquatic adaptation (paddle-like limbs). Surface shows cortical bone texture with visible cracks and some localized pitting.
Rock Matrix
Phosphate-rich sandy marl and soft limestone typical of the Moroccan phosphate mines; some residual matrix is likely adhered within the cracks.
Formation & Location
Ouled Abdoun Basin (specifically the Couche III or Couche II deposits), Khouribga, Morocco.
Size & Dimensions
Approximately 44 cm in length based on the included scale; this is a large specimen, suggesting a mature adult individual of significant size (~8-10 meters total body length).
Value & Rarity
Estimated Market Value
USD $800 - $1,500
Auction Estimate
USD $1,000 - $2,000
Rarity Assessment
Uncommon; while Mosasaur teeth and vertebrae are common from this locality, large, relatively intact limb bones (humeri/femora) are significantly less frequent.
Scientific Significance
Provides data on the taxonomic diversity and ontogeny of apex marine predators in the Tethys Ocean just prior to the K-Pg extinction event.
Preparation Recommendations
Stabilization of existing cracks with archival-grade consolidant (e.g., Paraloid B-72). Avoid water-based cleaning. Display on a custom-fitted cradle to distribute weight and prevent stress on the repaired mid-section.
Notable Features
The specimen exhibits the extreme shortening and widening of the humerus characteristic of advanced Mosasaurs, illustrating the evolutionary transition from terrestrial walking limbs to specialized marine flippers.
Notes
This is what I was told when purchased Hi there. All I know is what I was told when I purchased it in early 2000s that it was collected in the Khouribga region of Morocco in the early 1990s. It didn’t come with any documentation sorry so I’m not sure of the species