''Cymatoceras'' is a wide-ranging extinct genus from the nautilitacean cephalopod family,

Cymatoceratidae The Cymatoceratidae is a family of Mesozoic and early Cenozoic nautiloid cephalopods and the most abundant of this kind in the Cretaceous. They are characterized by ribbed, generally involute shells of varied form - coiled such that the outer w ...

. They lived from the

Late Jurassic The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 163.5 ± 1.0 to 145.0 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic strata.Owen 1987. In European lithostratigraphy, the ...

Late Oligocene The Chattian is, in the geologic timescale, the younger of two ages or upper of two stages of the Oligocene Epoch/ Series. It spans the time between . The Chattian is preceded by the Rupelian and is followed by the Aquitanian (the lowest stag ...

, roughly from 155 to 23 Ma. Fossilworks
/ref>Sepkoski, Jac
Sepkoski's Online Genus Database – Cephalopodes
/ref>

Species

The following species of ''Cymatoceras'' have been described: * ''C. albense'' * ''C. atlas'' * ''C. bayfieldi'' * ''C. bifidum'' * ''C. bifurcatum'' * ''C. carlottense'' * ''C. cenomanense'' * ''C. colombiana'' * ''C. crebricostatum'' * ''C. deslongchampsianum'' * ''C. eichwaldi'' * ''

C. elegans ''Caenorhabditis elegans'' () is a free-living transparent nematode about 1 mm in length that lives in temperate soil environments. It is the type species of its genus. The name is a blend of the Greek ''caeno-'' (recent), ''rhabditis'' ( ...

'' * ''C. hendersoni'' * ''C. hilli'' * ''C. honmai'' * ''C. hunstantonensis'' * ''C. huxleyanum'' * ''C. karakaschi'' * ''C. kayeanum'' * ''C. kossmati'' * ''C. loricatum'' * ''C. ludevigi'' * ''C. manuanensis'' * ''C. mikado'' * ''C. neckerianum'' * ''C. negama'' * ''C. neocomiense'' * ''C. pacificum'' * ''C. paralibanoticum'' * ''C. patagonicum'' * ''C. patens'' * ''C. perstriatum'' * ''C. picteti'' * '' C. pseudoatlas'' * '' C. pseudoelegans'' * '' C. pseudoneokomiense'' * ''C. pseudonegama'' * ''C. pulchrum'' * ''C. radiatum'' * ''C. renngarteni'' * ''C. sakalavum'' * ''C. sarysuense'' * ''C. savelievi'' * ''C. semilobatum'' * ''C. sharpei'' * ''C. tenuicostatum'' * ''C. tourtiae'' * ''C. tskaltsithelense'' * ''C. tsukushiense'' * ''C. virgatum'' * ''C. yabei''

Description

Its shell is generally subglobular, variably involute with a rounded whorl section. Sides and venter bear conspicuous ribs. The suture is only slightly sinuous and the siphuncle position is variable.Bernhard Kummel, 1964. Nautiloidea - Nautilida. Treatise on Invertebrate Paleontology Part K. Geol Soc of America and Univ Kans Press, Teichert & Moore (eds) ''Paracymatoceras'', coeval during the Late Jurassic and Early Cretaceous differs primarily in having a more sinuous suture. ''Neocymatoceras tsukushiense'' from the Oligocene

Ashiya Group Ashiya may refer to: * Ashiya, Hyōgo, Japan ** Ashiya University, Hyōgo * Ashiya, Fukuoka, Japan * Ashiya, a subcaste of Charans from Rajasthan, India * Mizuki Ashiya This is a list of characters from the manga and drama series, ''Hana-Kimi'' ...

of Japan, described by Kobayashi, 1954, has been reassigned to ''Cymatoceras''.

Fossil record

Fossils of ''Cymatoceras'' are found in marine strata from the

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 ...

until the

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but ...

(age range: from 155.7 to 23 million years ago.). Fossils are known from several localities: ;Jurassic Mexico ;Cretaceous Antarctica, Argentina, Armenia, Azerbaijan, Chile, Colombia ( Payandé, Tolima and La Guajira), France, Georgia, Germany, Greenland, India, Italy, Japan, Kazakhstan, Madagascar, Mexico, Morocco, Mozambique, Papua New Guinea, Poland, the Russian Federation, Switzerland, Tanzania, Turkmenistan, Ukraine, the United Kingdom, United States (California, New Mexico, Texas). ;Oligocene Japan

References

{{Taxonbar, from=Q5199382 Prehistoric nautiloid genera Late Jurassic genus first appearances Oligocene genus extinctions Mesozoic Antarctica Cretaceous animals of Africa Cretaceous animals of Asia Cretaceous cephalopods of Europe Jurassic cephalopods of North America Jurassic Mexico Cretaceous cephalopods of North America Cretaceous Mexico Cretaceous United States Cretaceous animals of South America Cretaceous Argentina Cretaceous Chile Cretaceous Colombia Fossil taxa described in 1884