Jydegaard Formation

Jydegaard Formation
Jydegaard Formation
Stratigraphic range: Late Berriasian-early Valanginian; ~
Type	Geological formation
Unit of	Nyker Group
Sub-units	Rødbjerg & Tornhøj Members
Underlies	Arnager Greensand Formation
Overlies	Robbedale Formation
Lithology
Primary	Claystone, sandstone
Location
Coordinates	55.1°N 14.8°E
Approximate paleocoordinates	47.2°N 21.4°E
Region	Bornholm
Country	Denmark
	Jydegaard Formation (Denmark)

The Jydegaard Formation (also spelled as 'Jydegård') is a geological formation dating to the Early Cretaceous, about 145-139 million years ago. It is on the island of Bornholm, Denmark. Vertebrate fossils have been found in the formation.[1]

Fossil content

Thin bone fragments have been uncovered that may belong to pterosaurs or birds.[1]

Dinosaurs

A tooth possibly belonging to a juvenile titanosaur has been found in the formation.[1]

Genus	Species	Location	Material	Description	Images
Dromaeosauroides[1]	D. bornholmensis[1]	Robbedale[1]	Two teeth and possible coprolites.[2]		Holotype tooth Life Reconstruction

Crocodylomorphs

Genus	Species	Location	Material	Description	Images
Pholidosaurus[1]	unknown	Robbedale[1]	A tooth tentatively referred to Pholidosaurus[3]		Possible tooth

Fish

Fish remains have been found in coprolites possibly belonging to the dromaeosaur Dromaeosauroides or marine turtles. Also, unidentified pycnodont jaws and two small stem-teleosteans have been uncovered. Amioid scales have also been revealed.[1]

Genus	Species	Location	Material
Lepidotes[1]	L. sp[1]	Robbedale[1]	Teeth, jaws and scales[1]
Hybodus[2]	unknown	Robbedale[2]	Teeth and scales[2]
Parvodus[1]	P. rugianus[4]	Robbedale[1]	Teeth, finspines and head "hooks"[1]
Pleuropholis[1]	P. serrata[5]	Robbedale[1]	unknown

Turtles

Unidentified turtle carapaces have been uncovered in the Formation.[1]

Lizards

A lower jaw from a lizard has been recovered from the formation.[1]

Bivalves

Genus	Species	Location	Material	Description	Images
Neomiodon[1]	unknown	Robbedale[1]	many specimens[1]	Neomiodon specimens are thought to be victim to a mass mortality such as poisoning.[1]
Viviparus[1]	unknown	Robbedale[1]	many specimens[1]	Viviparus specimens are thought to be victim to a mass mortality such as poisoning.[1]

Color key

Taxon	Reclassified taxon	Taxon falsely reported as present	Dubious taxon or junior synonym	Ichnotaxon	Ootaxon	Morphotaxon

Notes
Uncertain or tentative taxa are in small text; ~~crossed out~~ taxa are discredited.

References

Bonde, N.; Cristiansen, P. (2003). "New dinosaurs from Denmark". Comptes Rendus Palevol. 2 (13). doi:10.1016/51631-0683(03)00009-5.
Milàn, J.; Rasmussen, B. W.; Bonde, N. (2012). "Coprolites with prey remains from the Lower Cretaceous (Late Berriasian) Jydegaard Formation of Bornholm, Denmark" (PDF). New Mexico Museum of Natural History and Science. Bulletin. 57: 235–240.
Schwarz-Wings, D.; Rees, J.; Lindgren, J. (2009). "Lower Cretaceous Mesoeucrocodylians from Scandinavia (Denmark and Sweden)". Cretaceous Research. 30 (5): 1345. doi:10.1016/j.cretres.2009.07.011.
"Parvodus rugianus". Paleobiology Database. Retrieved 25 September 2013.
"Pleuropholis serrata". Paleobiology Database. Retrieved 25 September 2013.