Escuminac Formation

For homonymy, see Escuminac.

The Escuminac Formation is a geologic formation in Quebec. It preserves fossils dating back to the Frasnian, in the Devonian period.^[2][3]

Escuminac Formation
Stratigraphic range: Devonian (Middle Frasnian) 385–374 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Outcrops of the Escuminac Formation in Miguasha National Park
Type	Geological formation
Unit of	Miguasha Group[1]
Underlies	Bonaventure Formation[1]
Overlies	Fleurant Formation[1]
Location
Region	Quebec
Country	Canada

Description

A reconstruction of the paleoenvironment of the Escuminac Formation.

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.^[1] The main Miguasha exposures were named the 'René Bureau Cliffs' after the geologist and paleontologist.^[1] 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,^[4] the actinistian Miguashaia^[5] and the tetrapodomorph Euthenopteron.^[6]

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.^[1]

Fossil content

Vertebrates

Acanthodians

Acanthodians
Genus	Species	Presence	Material	Notes	Images
Diplacanthus	D. ellsi	[1]		A diplacanthiform.
	D. horridus	[1]		A diplacanthiform.
Homalacanthus	H. concinnus	[1]
Triazeugacanthus	T. affinis	Miguasha, Quebec.[1][7]	Thousands of specimens representing multiple ontogenetic stages.[7]

Actinopterygians

Actinopterygians
Genus	Species	Presence	Material	Notes	Images
Cheirolepis	C. canadensis	[1]

Jawless fish

Jawless fish
Genus	Species	Presence	Material	Notes	Images
Endeiolepis	E. aneri	[1]
Escuminaspis	E. laticeps	[1]
Euphanerops	E. longaevus	Miguasha.[1][8]	Over 3,500 specimens.[8]	A euphaneropid.
Levesquaspis	L. patteni	[1]

Placoderms

Placoderms
Genus	Species	Presence	Material	Notes	Images
Bothriolepis	B. canadensis	[1]		An antiarch.
Plourdosteus	P. canadensis	[1]		An arthrodire.

Sarcopterygians

Sarcopterygians
Genus	Species	Presence	Material	Notes	Images
Callistiopterus	C. clappi	[1]
Elpistostege	E. watsoni	[1]		A stegocephalian.
Eusthenopteron	E. foordi	[1]		A tristichopterid.
Fleurantia	F. denticulata	[1]		A lungfish.
Holoptychiidae	Holoptychiidae nov. sp.	[1]		A porolepiform.
Holoptychius	H. jarviki	[1]		A porolepiform.
Miguashaia	M. bureaui	Miguasha, Quebec.[1][9]		A coelacanth.
Quebecius	Q. quebecensis	[1]		A porolepiform.
Scaumenacia	S. curta	[1]		A lungfish.

Invertebrates

Arthropods

Arthropods
Genus	Species	Presence	Material	Notes	Images
Asmusia	A. membranacea	[1]		A clam shrimp.
Pterygotus	P. sp.	[10]		An eurypterid.
Petaloscorpio	P. bureaui	[1]		A scorpion.
Zanclodesmus	Z. willetti	[1][11]		A millipede.

Ctenophores

Ctenophores
Genus	Species	Presence	Material	Notes	Images
Daihuoides	D. jakobvintheri	Miguasha, Quebec.[12]	MHNM 24–01.[12]

Plants

Plants
Genus	Species	Presence	Material	Notes	Images
Archaeopteris	A. halliana	[1]
Barynophyton		[1]
Flabellofolium		[1]
Protobarynophyton		[1]
Spermasporites		[1]

See also

• Earth sciences portal
• Canada portal
• Paleontology portal

• List of fossiliferous stratigraphic units in Quebec