• Delorme Group (Lower Devonian)
• MOTH locality, Mackenzie Mountains, N.W.T.
• block containing 8 fish in Thelodonti (Drepanaspis and Furcacauda), Osteostraci (Superciliaspis), Acanthodii (Ischnacanthidae - one specimen, Lupopsyrus - one specimen, and Brochoadmones - two specimens), and Chondrichthyes (Obtusacanthus)
• 30 cm
• $500 plaster, painted

 

Close-up views of selected specimens from the Wonder Block:

UALVP 41491 & 41492 upper left
Ischnacanthid (41491) and osteostracan (41492)

UALVP 41493 & 41494 mid-left
Lupopsyrus (41493) and Brochoadmones (41494)

UALVP 41495 & 41496 mid-right
Brochoadmones (41495) and small fork-tailed thelodont Drepanolepis maerssae (41496)

UALVP 41496 mid-right, close-up of small fork-tailed thelodont Drepanolepis maerssae (41496)

UALVP 41488 upper right
Primitive chondrichthyan Obtusacanthus corroconis (41488)

References:

Adrain, J. M. and M. V. H. Wilson. 1994. Early Devonian cephalaspids (Vertebrata: Osteostraci: Cornuata) from the southern Mackenzie Mountains, N.W.T., Canada. Journal of Vertebrate Paleontology, 14(3):301-319.

Blais, S. A., L. A. Mackenzie, and M. V. H. Wilson. 2011. Tooth-like scales in Early Devonian eugnathostomes and the ‘outside-in’ hypothesis for the origins of teeth in vertebrates. Journal of Vertebrate Paleontology 31(6):1189-1199.

Hanke, G. F., and S. P. Davis. 2012. A reexamination of Lupopsyrus pygmaeus Bernacsek & Dineley, 1977 (Pisces, Acanthodii). Geodiversitas 34(3):469-487.

Hanke, G. F., and M. V. H. Wilson. 2004. New teleostome fishes and acanthodian systematics; pp. 187-214 in G. Arratia, M. V. H. Wilson, and R. Cloutier (eds.) Recent Advances in the Origin and Early Radiation of the Vertebrates. Verlag Friedrich Pfeil, Munich.

Hanke, G. F., and M. V. H. Wilson. 2006. Anatomy of the Early Devonian acanthodian Brochoadmones milesi based on nearly complete body fossils, with comments on the evolution and development of paired fins. Journal of Vertebrate Paleontology 26(3):526–537.

Hawthorn, J. R., M. V. H. Wilson, and A. B. Falkenberg. 2008. Development of the exoskeleton in Superciliaspis gabrielsei (Agnatha: Osteostraci). Journal of Vertebrate Paleontology 28(4):951-960.

Sahni, S., and M. V. H. Wilson. 2001. Extrinsic labyrinth infillings imply open endolymphatic ducts in Lower Devonian osteostracans, acanthodians, and putative chondrichthyans. Journal of Vertebrate Paleontology 21(4):660-669.

Wilson, M. V. H., T. Märss, and G. F. Hanke. 2007. Paired fins of jawless vertebrates and their homologies across the agnathan-gnathostome transition; pp. 122-149, plates 23-24 in H.-D. Sues and J. Anderson (eds.), Major Transitions in Vertebrate Evolution. Indiana University Press, Bloomington.