Doryaspis

Doryaspis ("Dart Shield") (also known by its synonym, "Lyktaspis") is an extinct genus of primitive jawless fish that lived in the Devonian period. Fossils have been discovered in Spitsbergen.

Doryaspis
Temporal range: Early Devonian
Reconstruction of D. nathorsti
Scientific classification
Kingdom:
Animalia
Phylum:
Chordata
Class:
†Pteraspidomorphi
Order:
†Pteraspidiformes
Family:
†Doraspididae
Genus:
†Doryaspis

White 1935
Type species
Doryaspis nathorsti
(Lankester 1884) White 1935
Species
  • D. arctica Pernègre 2002
  • D. groenhorgensis Pernègre 2005
  • D. minor (Heintz 1960)
  • D. nathorsti (Lankester 1884) White 1935
Synonyms
  • Scaphaspis
  • Lyktaspis Heintz 1968

The animals had a canteen-shaped body armor, and had large branchial plates that extended out and curved downward in a triangular shape, very similar to those of the pycnosteids. An element of the median oral plates (that would correspond to the lower lip or chin in gnathostomes) extends out in a long rod-shaped appendage, called the "pseudorostrum." The tail is long and slender, and has large rows of thick scales.

In the type species, D. nathorsti, the lateral edges of the branchial plates and of the pseudorostrum are serrated. The second species, D. arctica, is smaller, and lacks serrated edges.

  • Reconstruction of recently discovered species, D. arctica
  • Reconstruction of the type species, D. nathorsti

References
    • THE GENUS DORYASPIS WHITE (HETEROSTRACI) FROM THE LOWER DEVONIAN OF VESTSPITSBERGEN, SVALBARD
    • Long, John A. The Rise of Fishes: 500 Million Years of Evolution, Baltimore: The Johns Hopkins University Press, 1996. ISBN 0-8018-5438-5


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