Dunkleosteus

Dunkleosteus was a prehistoric arthrodire. It was a primitive fish from the later Devonian period, about 382.31 to 358.86 million years ago.^[1] It was a heavily armoured placoderm. Fossils have been found in Morocco, Africa, Poland, Belgium, China, and the USA. This fish was a pelagic creature living in open waters, and one of the first vertebrate apex predators of any ecosystem.^[2]

Dunkleosteus Temporal range: Devonian, 387.2–358.86 Ma PreꞒ Ꞓ O S D C P T J K Pg N Possible Early Givetian record
Dunkleosteus skull, Queensland Museum
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Subphylum:	Vertebrata
Class:	†Placodermi
Order:	†Arthrodira
Family:	†Dunkleosteidae
Genus:	†Dunkleosteus Lehman, 1956
Type species
†Dunkleosteus terrelli Newberry, 1873

Dunkleosteus first appeared in the Late Silurian, and the group became extinct during the transition from the Late Devonian to the Late Carboniferous, leaving no descendants. It lasted barely 50 million years compared to the 400 million year-long history of sharks. It preyed on Stethacanthus and Cladoselache.

One new species from 2023, D. tuderensis, was named based on an infragnathal from the Famennian of the Tver Oblast, Russia.^[3]

Description

Life restorations of three species

This top predator was up to 11.5 ft (3.5 m) long and had large, scissor-like cutting jaws with serrated, razor-sharp bones but no teeth. Its skull was over 2 feet (65 cm) long. It had a jointed neck, a normal fish tail, a scale-less body, and hinged body shields.

The "shrunken" reconstruction of Dunkleosteus

Species

• †D. amblyodoratus Carr & Hlavin, 2010
• †D. belgicus (?) (Newberry, 1873)
• †D. denisoni (Kulczycki, 1957)
• †D. magnificus (Hussakof & Bryant, 1919)
• †D. marsaisi Lehmann, 1956
• †D. missouriensis (Branson, 1914)
• †D. newberryi (Clarke, 1885)
• †D. raveri Carr & Hlavin, 2010
• †D. terrelli (Newberry, 1873 [originally Dinichthys])
• †D. tuderensis Lebedev et. al., 2023^[3]