Haplocerataceae
Encyclopedia
Haplocerataceae is a superfamily of ammonoid cephalopods belonging to the Ammonitida
that unites three families, the Strigoceratidae
, Oppeliidae
, and Haploceratidae
, listed below.
The Haplocerataceae begins with all three families in the lower Middle Jurassic
, Bajocian
. The Strigoceratidae is limited to the Bajocian but the Oppeliidae, and Haploceratidae extend through the remaining Jurassic, well into the Cretaceous
; the Oppeliidae into the middle Albian
, the Haplocertidae only into the Valanginian
.
are paired and differ between families and have been found in situ in e.g. Oppelia subrudiata
and in Pseudolissoceras.
Superfamily Haplocerataceae Zittel, 1884
Ammonitida
The Ammonitida is an order of more highly evolved ammonoid cephalopods from the Jurassic and Cretaceous time periods, commonly with intricate ammonitic sutures....
that unites three families, the Strigoceratidae
Strigoceratidae
The Strigoceratidae is a family in the ammonitid superfamily Haplocerataceae, restricted to the lower Middle Jurassic, Bajocian stage, possibly derived from the Hammitoceratidae...
, Oppeliidae
Oppeliidae
Oppeliidae are compressed to oxyconic, sculptured Haplocerataceae, either unkeeled, unicarinate, bicarinate, or tricarinate; with sutures in great variety, but ribbing usually more or less falcoid or falcate...
, and Haploceratidae
Haploceratidae
The Haploceratidae is one of the families to go to form the Haplocerataceae, a superfamily in the ammonitina; which according to Donovan et al can be derived from the Taramelliceratinae, a subfamily of the Oppeliidae....
, listed below.
The Haplocerataceae begins with all three families in the lower Middle Jurassic
Middle Jurassic
The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from 176-161 million years ago. In European lithostratigraphy, rocks of this Middle Jurassic age are called the Dogger....
, Bajocian
Bajocian
In the geologic timescale, the Bajocian is an age or stage in the Middle Jurassic. It lasted from approximately 171.6 Ma to around 167.7 Ma . The Bajocian age succeeds the Aalenian age and precedes the Bathonian age....
. The Strigoceratidae is limited to the Bajocian but the Oppeliidae, and Haploceratidae extend through the remaining Jurassic, well into the Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
; the Oppeliidae into the middle Albian
Albian
The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous epoch/series. Its approximate time range is 112.0 ± 1.0 Ma to 99.6 ± 0.9 Ma...
, the Haplocertidae only into the Valanginian
Valanginian
In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 140.2 ± 3.0 Ma and 136.4 ± 2.0 Ma...
.
Diagnosis
Haplocerataceae are typically compressed, discoidal Ammontida that may be keeled or unkeeled, tending to be oxyconic, with usually falcoid or falcate ribbing. The aptychiAptychus
An aptychus is a type of marine fossil, a hard anatomical structure like a curved shelly plate, which was part of the body of an ammonite. Paired aptychi have, on rare occasions, been found at or within the aperture of ammonite shells....
are paired and differ between families and have been found in situ in e.g. Oppelia subrudiata
Oppelia
Oppelia is a haploceratcean ammonite and type genus for the Oppeliidae that lived during the Middle Jurassic between 170 and 164 million years ago. Shells of Oppelia are involute with a small to moderate size umbilicus, bluntly rounded to sharp venter, and deeply impressed dorsum. Sides are...
and in Pseudolissoceras.
Taxonomy
The Origin of the Haplocerataceae is undetermined but it is likely all three component families have their beginnings in the Hammatoceratidae in the middle Bajocian. None of the Haplocerataceae is though to have given rise to any subsequent group.Superfamily Haplocerataceae Zittel, 1884
- Family HaploceratidaeHaploceratidaeThe Haploceratidae is one of the families to go to form the Haplocerataceae, a superfamily in the ammonitina; which according to Donovan et al can be derived from the Taramelliceratinae, a subfamily of the Oppeliidae....
Zittel, 1884- Genus LissocerasLissocerasLissoceras is an involute, smooth or finely vetrolaterally ribbed, ammonite with a blunt, un-keeled venter, included in the Haploceratidae, that lived from the Lower Bajocian - Middle Oxfordian in what is now Europe, south Asia, and southern Alaska.Lissoceratoides, once considered to be a subgenus...
Bayle, 1879 - Genus GlochicerasGlochicerasGlochiceras is a haploceratid ammonite characterized by a small, smooth, compressed, evolute shells with large lappets and a median lateral groove...
Hyatt, 1900 - Genus HaplocerasHaplocerasHaploceras is a late Upper Jurassic ammonoid cephalopod and type for the Haploceratidae, similar to Lissoceras but with a broader whorl section and small blunt lappets and a blunt rostrum; some species with feeble ventral folds on body chamber...
Zittel, 1870 - Genus NeolissocerasNeolissocerasNeolissoceras is a haploceratid ammonite with a smooth, compressed, flat-sided shell with a flatly rounded venter and distinct umbilical margin, from the Upper Jurassic - Lower Cretaceous of southern Europe, Madagascar, and India.-References:Arkell et al, 1957 Mesozoic Ammonoidea, Treatise on...
Spath, 1923
- Genus Lissoceras
- Family OppeliidaeOppeliidaeOppeliidae are compressed to oxyconic, sculptured Haplocerataceae, either unkeeled, unicarinate, bicarinate, or tricarinate; with sutures in great variety, but ribbing usually more or less falcoid or falcate...
Bonarelli, 1894- Subfamily Aconeceratinae (Spath, 1923)
- Genus AconecerasAconecerasAconiceras is an early Cretaceous ammonite included in the oppeliid subfamily Aconeceratidae, characterized by an involute, high-whorled, flat-sided shell that bears a finely serrate keel along the venter. Sutures have narrower and deeper elements than in Protaconeceras. Aconeceras has been found...
Hyatt, 1903 - Genus Gyaloceras Whitehouse, 1927
- Genus Koloceras Riccardi et al., 1987
- Genus Sanmartinoceras
- Genus Aconeceras
- Subfamily Hecticoceratinae Spath, 1925
- Genus HecticocerasHecticocerasHecticoceras is an ammonite genus belonging to the haploceratacean family Oppeliidae, that lived during the Middle and Late Jurassic, from the early Callovian to the early Oxfordian. Hecticoceras may be seen as a series of some nine subgenera, beginning with the lower Callovian H. and H. and...
Bonarelli, 1893
- Genus Hecticoceras
- Subfamily Mazapilitinae Spath, 1928
- Genus Submazapilites Cantu-Chapa, 1962
- Subfamily Streblitinae Spath, 1925
- Genus Bornhardticeras Böhm & Riedel, 1933
- Genus Cyrtosiceras Hyatt, 1900
- Genus Substreblites Spath, 1925
- Genus UhligitesUhligitesUligites is an oppeliid ammonite included in the subfamily Streblitinaethat lived during the latest part of the Jurassic and earliest Cretaceous; from about 150 to 140 m.y.a....
Kilian, 1913
- Subfamily incertae sedisIncertae sedis, is a term used to define a taxonomic group where its broader relationships are unknown or undefined. Uncertainty at specific taxonomic levels is attributed by , , and similar terms.-Examples:*The fossil plant Paradinandra suecica could not be assigned to any...
- Genus Naramoceras McNamara, 1985
- Subfamily Aconeceratinae (Spath, 1923)
- Family StrigoceratidaeStrigoceratidaeThe Strigoceratidae is a family in the ammonitid superfamily Haplocerataceae, restricted to the lower Middle Jurassic, Bajocian stage, possibly derived from the Hammitoceratidae...
Buckman, 1924- Genus OecoptychiusOecoptychiusOecoptychius is an extinct genus from a well known subclass of fossil cephalopods, the ammonites. It lived during the Jurassic Period, which lasted from approximately 200 to 145 million years ago....
- Genus Phlycticeras Hyatt, 1900
- Genus Strigoceras Quenstedt, 1886
- Genus Oecoptychius