The Escuminac Formation is a geologic formation in Quebec. It preserves fossils dating back to the Frasnian, in the Devonian period.

Description

Miguasha National Park is located within this formation along the estuary of the Restigouche River on the south coast of the Gaspé Peninsula. The fossil biota from the Park is thus referred to as the Miguasha biota. The main Miguasha exposures were named the 'René Bureau Cliffs' after the geologist and paleontologist. This formation is sufficiently rich that some material could be sacrificed for microanatomical and histological study through thin sectioning; this was done, among others, for the actinopterygian Cheirolepis, the actinistian Miguashaia and the tetrapodomorph Euthenopteron.

The formation's depositional environment has been variously considered as lacustrine, estuarine, coastal marine or marine, though evidence from the fossil assemblage, stratigraphic and sedimentological setting, and geochemistry of the sedimentary rocks and bones suggests an estuarine interpretation is most fitting.

Fossil content Vertebrates Acanthodians Acanthodians Genus Species Presence Material Notes ImagesDiplacanthusD. ellsi A diplacanthiform. D. horridus A diplacanthiform. HomalacanthusH. concinnusTriazeugacanthusT. affinisMiguasha, Quebec.Thousands of specimens representing multiple ontogenetic stages.

Actinopterygians Actinopterygians Genus Species Presence Material Notes Images CheirolepisC. canadensis

Jawless fish Jawless fish Genus Species Presence Material Notes ImagesEndeiolepisE. aneriEscuminaspisE. laticeps EuphaneropsE. longaevus Miguasha.Over 3,500 specimens. A euphaneropid.LevesquaspisL. patteni

Placoderms Placoderms Genus Species Presence Material Notes Images BothriolepisB. canadensis An antiarch.PlourdosteusP. canadensisAn arthrodire.

Sarcopterygians Sarcopterygians Genus Species Presence Material Notes ImagesCallistiopterusC. clappiElpistostegeE. watsoniA stegocephalian.EusthenopteronE. foordiA tristichopterid.FleurantiaF. denticulataA lungfish.HoloptychiidaeHoloptychiidae nov. sp.A porolepiform.HoloptychiusH. jarvikiA porolepiform. MiguashaiaM. bureaui Miguasha, Quebec. A coelacanth.QuebeciusQ. quebecensisA porolepiform.ScaumenaciaS. curtaA lungfish.

Invertebrates Arthropods Arthropods Genus Species Presence Material Notes Images AsmusiaA. membranacea A clam shrimp. PterygotusP. sp.An eurypterid.PetaloscorpioP. bureauiA scorpion.ZanclodesmusZ. willettiA millipede.

Ctenophores Ctenophores Genus Species Presence Material Notes Images DaihuoidesD. jakobvintheri Miguasha, Quebec.MHNM 24–01.

Plants Plants Genus Species Presence Material Notes Images ArchaeopterisA. halliana BarynophytonFlabellofoliumProtobarynophytonSpermasporites

See also

List of fossiliferous stratigraphic units in Quebec

References