Massive, 11.6" Tractor Ammonite (Douvilleiceras) Fossil - Madagascar

This is a huge, 11.6" wide Douvilleiceras ammonite from the Upper Cretaceous of Madagascar. This genus of ammonites has earned the local name "Tractor Ammonites", due to their distinctively bumpy surface and pronounced ridges making them resemble a tractor tire. This particular example is one of the largest I've seen and is nearly 6.1" thick.

Comes with a display stand.

About Ammonites

Ammonites were ancient marine cephalopods, similar to today's squids and octopuses, but with a defining feature: their distinctive, tightly coiled spiral shells. These shells, resembling those of modern nautiluses, served as both a protective home and a buoyancy aid, allowing ammonites to navigate the prehistoric seas with ease. First emerging around 240 million years ago in the Triassic Period, ammonites thrived for over 175 million years, adapting through numerous forms and sizes. As predatory creatures, they likely fed on smaller marine organisms, using their tentacles to capture prey. However, their long reign came to an end 65 million years ago at the close of the Cretaceous, coinciding with the mass extinction event that also eliminated the dinosaurs.

What an ammonite would have looked like while alive.
What an ammonite would have looked like while alive.
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DETAILS
SPECIES
Douvilleiceras mammilatum
LOCATION
Mahajanga Province, Madagascar
SIZE
11.6" wide, up to 6.1" thick
ITEM
#197179
GUARANTEE
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