''Acrioceras'' is an extinct genus of cephalopods belonging to the

ammonite Ammonoids are extinct, (typically) coiled-shelled cephalopods comprising the subclass Ammonoidea. They are more closely related to living octopuses, squid, and cuttlefish (which comprise the clade Coleoidea) than they are to nautiluses (family N ...

subclass. with and (1996), ''Mollusca 4 Revised, Cretaceous Ammonoidea'', vol. 4, in ''Treatise on Invertebrate Paleontology'', Part L (Roger L. Kaesler ed.), Boulder, Colorado: The Geological Society of America & Lawrence, Kansas: University of Kansas Press, pp. 223, 224.

Description

A spire of one or two loosely coiled whorls followed by a short or long, straight or curved shaft, terminal hook, and short and or long final shaft. The ribs are generally fine and untuberculate, but sometimes the major ribs are enlarged and are carrying one to three tubercles. The ribs are single on the spire or the shaft but may branch from umbilical tubercles on the hook and the final shaft. The dorsum tends to become flat and the dorsolateral margin to become angular on the shaft and the hook.

Distribution

Fossils of ''Acrioceras'' have been found in: * Barremian Formation,

Brestak Brestak (in Bulgarian: Брестак) is a village in northern Bulgaria, Valchi Dol Municipality, Varna Province Varna Province (), formerly known as Varna okrug, is a province in eastern Bulgaria, one of the 28 Bulgarian provinces. It compri ...

Bulgaria Bulgaria, officially the Republic of Bulgaria, is a country in Southeast Europe. It is situated on the eastern portion of the Balkans directly south of the Danube river and west of the Black Sea. Bulgaria is bordered by Greece and Turkey t ...

* Ono Formation,

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

Paja Formation The Paja Formation (, K1p, Kip, Kimp, b3b6p) is an Early Cretaceous formation (geology), geologic formation of central Colombia. The formation extends across the northern part of the Altiplano Cundiboyacense, the Colombian emeralds#Western belt, W ...

Colombia Colombia, officially the Republic of Colombia, is a country primarily located in South America with Insular region of Colombia, insular regions in North America. The Colombian mainland is bordered by the Caribbean Sea to the north, Venezuel ...

Barremian The Barremian is an age in the geologic timescale (or a chronostratigraphic stage) between 125.77 Ma (million years ago) and 121.4 ± 1.0 Ma (Historically, this stage was placed at 129.4 million to approximately 125 million years ago) It is a ...

Provence Provence is a geographical region and historical province of southeastern France, which stretches from the left bank of the lower Rhône to the west to the France–Italy border, Italian border to the east; it is bordered by the Mediterrane ...

France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...

Georgia Georgia most commonly refers to: * Georgia (country), a country in the South Caucasus * Georgia (U.S. state), a state in the southeastern United States Georgia may also refer to: People and fictional characters * Georgia (name), a list of pe ...

* Subway Formation,

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

* Maiolica Formation,

Italy Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...

* Ishido and Inagoe Formations,

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

* San Lucas Formation,

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

* Taboulouart Formation,

Morocco Morocco, officially the Kingdom of Morocco, is a country in the Maghreb region of North Africa. It has coastlines on the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to Algeria–Morocc ...

Hauterivian The Hauterivian is, in the geologic timescale, an age in the Early Cretaceous Epoch or a stage in the Lower Cretaceous Series. It spans the time between 132.6 ± 2 Ma and 125.77 (million years ago). The Hauterivian is preceded by the Valangi ...

Slovakia Slovakia, officially the Slovak Republic, is a landlocked country in Central Europe. It is bordered by Poland to the north, Ukraine to the east, Hungary to the south, Austria to the west, and the Czech Republic to the northwest. Slovakia's m ...

* Makatini Formation,

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

Murcia Murcia ( , , ) is a city in south-eastern Spain, the Capital (political), capital and most populous city of the autonomous community of the Region of Murcia, and the Ranked lists of Spanish municipalities#By population, seventh largest city i ...

Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...

References

External links

* * * Ancyloceratina Ammonitida genera Barremian life Hauterivian life Ammonites of Africa Cretaceous Morocco Fossils of Morocco Ammonites of Asia Fossils of Japan Early Cretaceous ammonites of Europe Cretaceous France Fossils of France Cretaceous Germany Fossils of Germany Cretaceous Italy Fossils of Italy Fossils of Slovakia Cretaceous Spain Fossils of Spain Early Cretaceous ammonites of North America Cretaceous California Fossils of the United States Cretaceous Mexico Fossils of Mexico Ammonites of South America Cretaceous Colombia Fossils of Colombia Paja Formation Fossil taxa described in 1900 {{Ammonite-stub