Aulacostephanidae is an extinct ammonoid cephalopod family belonging to the superfamily
Perisphinctoidea
Perisphinctoidea, formerly Perisphinctaceae, is a superfamily of Middle Jurassic (Bajocian) to Lower Cretaceous (Barremian) ammonites, commonly with evolute shells with strong ribbing that typically divides about mid flank before crossing the ven ...
. These fast-moving nektonic carnivores lived during the Upper
Jurassic
The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The J ...
period, from the
Oxfordian to
Tithonian
In the geological timescale, the Tithonian is the latest age of the Late Jurassic Epoch and the uppermost stage of the Upper Jurassic Series. It spans the time between 152.1 ± 4 Ma and 145.0 ± 4 Ma (million years ago). It is preceded by the K ...
ages.
Genera
Genera within this family include:
[Paleobiology Database]
Sepkoski Online
*''Aulacostephanus
''Aulacostephanus'' is an extinct ammonoid cephalopod genus from the Upper Jurassic Tithonian belonging to the perisphinctoidean family Aulacostephanidae.
''Aulacostephanus'' produced a discoidal, strongly ribbed, evolute shell of moderate s ...
''
*''Pictonia
''Pictonia'' is an extinct ammonoid cephalopod genus belonging to the family Aulacostephanidae. These fast-moving nektonic carnivores lived during the Jurassic period, Kimmeridgian age (from 152.1 to 157.3 mya).[Rasenia
''Rasenia'' is an extinct ammonoid cephalopod genus belonging to the superfamily Perisphinctoidea. These fast-moving nektonic carnivores lived during the Upper Jurassic period, in the Kimmeridgian and Tithonian ages.
Etymology
This genus gets i ...]
''
*''Ringsteadia
''Ringsteadia'' is a Jurassic
The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic ...
''
References
* JOHN K. WRIGHT
The Aulacostephanidae (Ammonoidea) of the Oxfordian/Kimmeridgian boundary beds (Upper Jurassic) of southern England
Ammonitida families
Perisphinctoidea
Jurassic ammonites
Ammonites of Europe
Kimmeridgian first appearances
Late Jurassic extinctions
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