Solnhofen Gyrodus sp.
Place of discovery: Langenaltheim, Langenaltheimer Haardt; Solnhofener Revier/ Germany
Lithostratigraphy: Lower Tithonian, White Jurassic Group, Altmühltal Formation, Upper Solnhofen Subformation
Biostratigraphy: Hybonotum zone, rueppelianus subzone, rueppelianus horizon
Age: approx. 150.8 – 152 million years +/- 2 million years
Size plate and counter plate: 120 x 100 cm
Size of fossil: approx. 90 cm (largest size)
Showpiece: Giant “moonfish” – a fossil icon from the Upper Jurassic of Solnhofen.
Authentic – in original matrix, not reburied. With proof of provenance.
Offered on behalf of the customer. RESERVED
Gyrodus – The specialized hard parts specialist of the Solnhofen archipelago
The genus Gyrodus belongs to the order Pycnodontiformes and is a striking representative of the specialized fish fauna of the Solnhofen limestones. Its high-backed, almost circular body shape clearly distinguishes it from the spindle-shaped predatory fish of the open water. Gyrodus occupied the ecological niche of a “durophagous” consumer that specialized in cracking hard-shelled food.
Scientific classification and morphology
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- Adaptation to the reef biotope: The laterally strongly flattened, disc-shaped form enabled a high degree of maneuverability in the complex structures of the sponge and coral reefs that bordered the lagoons.
- Plaster tooth dentition: The most striking feature of Gyrodus is its specialized dentition. It consists of several rows of roundish, flat cobblestone teeth on the vomer (plowshare bone) and the prearticulars (lower jaw bones), which functioned like a grinder for breaking up shells, corals or crustaceans.
- Fin fringe: The dorsal and anal fins are elongated and form an almost symmetrical fringe on the posterior third of the body, which is typical of this evolutionary line.
The fine details – what collectors look out for:
- Plaster tooth batteries: In high-quality finds, the shiny tooth batteries in the skull area are often visible as a composite. The preservation of these hard tooth structures is considered an important diagnostic feature.
- Partial armor: In contrast to the fully armored Dapedium species, often only the front part of the trunk is covered with massive scale bars, while the rear part was unscaled. As a result, the bone structure is preserved in the anterior part and the impression of the soft tissue in the posterior part.
- Caudal fin: The strong, sickle-shaped caudal fin is often very distinctively developed and forms an aesthetic end to the body contour in well-preserved specimens.
A highlight for every Solnhofen collection
Gyrodus is one of the iconic fossils of the Jurassic Sea and is highly sought after by collectors due to its aesthetics. A fossil like this is not just an investment, but a window into a time when Bavaria was still a subtropical island paradise.
