''Pleuronautilus'' is a nautiloid genus; family Tainoceratidae, order

Nautilida The Nautilida constitute a large and diverse order of generally coiled nautiloid cephalopods that began in the mid Paleozoic and continues to the present with a single family, the Nautilidae which includes two genera, ''Nautilus'' and ''Allonauti ...

.Pleuronautilus- Paleodb
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Description

The shell is evolute, discoidal; whorl section subquadrade, flanks generally straight but may converge toward the venter. Inner flanks have course ribbing, outer have rows of nodes. Sutures have shallow ventral, lateral, and dorsal lobes. Its siphuncle is small and approximately central.

Fossil records

''Pleuronautilus'' has been found in Upper

Permian The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleoz ...

marine

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

in Armenia, China, and Iran, sometimes associated with orthocerids, ammonoids, and other nautilids as well as other invertebrates; in Upper Permian offshore mudstone and calcareous siltstone in the northern

Caucasus The Caucasus () or Caucasia (), is a region between the Black Sea and the Caspian Sea, mainly comprising Armenia, Azerbaijan, Georgia, and parts of Southern Russia. The Caucasus Mountains, including the Greater Caucasus range, have historically ...

, and in upper Lower Permian marine sediments in

Tajikistan Tajikistan (, ; tg, Тоҷикистон, Tojikiston; russian: Таджикистан, Tadzhikistan), officially the Republic of Tajikistan ( tg, Ҷумҳурии Тоҷикистон, Jumhurii Tojikiston), is a landlocked country in Centr ...

with grypoceratids and pronoritids. It has been found also in Lower

Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period ...

black marine calcareous shale in

Afghanistan Afghanistan, officially the Islamic Emirate of Afghanistan,; prs, امارت اسلامی افغانستان is a landlocked country located at the crossroads of Central Asia and South Asia. Referred to as the Heart of Asia, it is bordere ...

with orthocerid, aulacocerid, phylloceratitd and ceratitid cephalopod genera and in early Upper deltaic shale and marl with ceratitids, pelecypods, and gastropods in Slovenia; and mid upper offshore mustone with '' Paranautilus'' and ''

Rhacophyllites ''Rhacophyllites'' is an extinct genus of cephalopods belonging to the family Discophyllitidae.Treatise on Invertebrate Paleontology Part L Mollusca 4, Ammonoidea, 1957 These nektonic carnivores lived during the Triassic period, from Carnian to ...

'' and ceratitids in western

Nevada Nevada ( ; ) is a U.S. state, state in the Western United States, Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. N ...

Species

Species within this genus include: * †''Pleuronautilus alaskensis'' Kummel 1953 * †''Pleuronautilus changxingensis'' Zhao et al. 1978 * †''Pleuronautilus cooperi'' Miller 1945 * †''Pleuronautilus costalis'' Shimansky 1965 * †''Pleuronautilus dzhagadzurensis'' Zakharov 1989 * †''Pleuronautilus dzhulfensis'' Shimansky 1965 * †''Pleuronautilus gaudryi'' von Mojsisovics 1902 * †''Pleuronautilus gregarius'' Miller 1945 * †''Pleuronautilus incertus'' Abich 1878 * †''Pleuronautilus latissimus'' Waagen 1879 * †''Pleuronautilus lepsiusi'' von Mojsisovics 1902 * †''Pleuronautilus linchengense'' Yi 1933 * †''Pleuronautilus loczyi'' Fliegel 1901 * †''Pleuronautilus magnicostatus'' Miller 1945 * †''Pleuronautilus magnus'' Zheng 1984 * †''Pleuronautilus mariani'' Airaghi 1902 * †''Pleuronautilus megaporus'' Miller 1945 * †''Pleuronautilus mosis'' Mojsisovics 1882 * †''Pleuronautilus multicostatus'' Etheridge Jr. 1907 * †''Pleuronautilus mutatus ''Miller 1945 * †''Pleuronautilus praecursor'' Girty 1909 * †''Pleuronautilus qinghaianus'' Wang and Chen 1979 * †''Pleuronautilus russkiensis'' Zakharov 1978 * †''Pleuronautilus shumardianus'' Girty 1909 * †''Pleuronautilus sumatrensis'' Fliegel 1901 * †''Pleuronautilus venustus'' Reed 1944 * †''Pleuronautilus verae'' Arthaber 1900 * †''Pleuronautilus yahagiensis'' Ehiro 1995 * †''Pleuronautilus zhongyingensis'' Zheng 1984

References

*Bernhard Kummel, 1964. Nautiloidea-Nautilida. Treatise on Invertebrate Paleontology, Part K. Geological Soc. of America and University of Kansas press. Teichert and Moore (eds) * Bernhard Kumme
American Triassic Coiled Nautiloids
{{Taxonbar, from=Q7204786 Nautiloids Carboniferous first appearances Triassic extinctions Prehistoric nautiloid genera