Genus
Valid Extinct

Spicomellus

Maidment et al. 2021

Spicomellus is an extinct genus of unusual early ankylosaurian dinosaur from the El Mers III Formation of Morocco. The genus contains a single species, Spicomellus afer, representing the oldest named definitive ankylosaur. The species was initially described in 2021 based on a single rib with fused osteoderms, rendering its life appearance and relationships uncertain. In 2025, several additional bones, including osteoderms and cranial and postcranial remains, were described, revealing that it bears a unique array of spines over the body, including extremely elongated spikes around the neck and pelvis. It likely had a tail weapon, making it the oldest known ankylosaur with this structure.

Temporal range
Triassic
Jurassic
Cretaceous
Paleogene
Neogene
252 201 145 66 0 Ma
PBDB occurrences
1
Group
Dinosaures
Herbivore Ground dwelling, gregarious Terrestrial
Spicomellus
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Wikimedia
PBDB ↗ Wikipedia ↗
Classification
Dinosauria Unranked clade
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Ornithischia Unranked clade
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Parapredentata Unranked clade
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Saphornithischia Unranked clade
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Prionodontia Unranked clade
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Genasauria Unranked clade
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Thyreophora Unranked clade
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Thyreophoroidea Superfamily
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Eurypoda Unranked clade
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Ankylosauria Unranked clade
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Spicomellus Genus
Fossil sites 1 geolocated sites
Distribution
Top countries
🇲🇦 Morocco
1
Geological formations
El Mers III
1
Temporal distribution
Callovian (165.3–161.5 Ma)
1
Species (1)
Spicomellus afer 168 Ma
Images 1
Bibliography
Original description
S. C. R. Maidment, S. J. Strachan, and D. Ouarhache, T. M. Scheyer, E. E. Brown, V. Fernandez, Z. Johanson, T. J. Raven, P. M. Barrett. 2021. Bizarre dermal armour suggests the first African ankylosaur. Nature Ecology and Evolution 5:1576-1581 DOI ↗
Bibliography (1)
S. C. R. Maidment, S. J. Strachan, and D. Ouarhache, T. M. Scheyer, E. E. Brown, V. Fernandez, Z. Johanson, T. J. Raven, P. M. Barrett. 2021. Bizarre dermal armour suggests the first African ankylosaur. Nature Ecology and Evolution 5:1576-1581 DOI ↗