''Mariella'' is an
ammonoid
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 ...
genus, named by Nowak (1916) from the upper
Albian
The Albian is both an age (geology), age of the geologic timescale and a stage (stratigraphy), stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early Cretaceous, Early/Lower Cretaceous epoch (geology), Epoch/s ...
and
Cenomanian
The Cenomanian is, in the International Commission on Stratigraphy's (ICS) geological timescale, the oldest or earliest age (geology), age of the Late Cretaceous epoch (geology), Epoch or the lowest stage (stratigraphy), stage of the Upper Cretace ...
stages of the mid
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...
, included in the
Turrilitidae
Turrilitidae is a family of extinct heteromorph ammonite cephalopods. All members had shells that coiled helically that tended to resemble auger shells. The ecological roles turrilitids played is largely unknown, as experts are still speculati ...
. Its type is ''Turrilites bergeri''
Description
''Mariella'' resembles ''
Turrilites
''Turrilites'' is a genus of helically coiled ammonoid cephalopods from the lower part of the Upper Cretaceous (Cenomanian and Turonian); generally included in the Ancyloceratina. Previously (Arkell, 1957) it was included in the ammonoid suborde ...
'' in general form. The shell is asymmetric, closely wound in a long expanding trochoidal spire. Ribs are slightly oblique and are rather feeble, each with 4 more or less equally spaced tubercles. ''Turrilites'' differs primarily in being more strongly ribbed and in having a more oval aperture.
Distribution
Fossils of ''Mariella'' have been found in Angola, Antarctica, Australia, Brazil, Canada (British Columbia), Colombia (
Hiló Formation
The Hiló Formation (, Kih) is a formation (geology), geological formation of the Altiplano Cundiboyacense, Cordillera Oriental (Colombia), Eastern Ranges of the Colombian Andes. The predominantly shale formation dates to the Middle Cretaceous per ...
), France, Germany, Iran, Japan, Kazakhstan, Madagascar, Mexico, Mozambique, New Zealand, South Africa, Spain, Switzerland, Turkmenistan, Ukraine, the United Kingdom, and the United States (California, Texas, Oregon).
[''Mariella'']
at Fossilworks
Fossilworks was a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database, a large relational database assembled by hundreds of paleontologists from around the world.
History
Fossilworks was cr ...
.org
References
Further reading
*
{{Taxonbar, from=Q6763154
Ammonitida
Albian genus first appearances
Cenomanian genus extinctions
Ammonites of South America
Cretaceous Brazil
Cretaceous Colombia
Ammonites of Australia
Cretaceous animals of Australia
Ammonites of Antarctica
Late Cretaceous ammonites of North America
Cretaceous Canada
Cretaceous Mexico
Cretaceous United States
Cretaceous Africa
Cretaceous Asia
Late Cretaceous ammonites of Europe