| Title | Douvilleiceratid ammonites from the lower to middle Albian (Lower Cretaceous) Yezo Group of Hokkaido, Japan, and a revision of the genus Douvilleiceras |
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| Author | Futakami, M; Haggart, J W |
| Source | Cretaceous Research vol. 88, 2017 p. 273-292, https://doi.org/10.1016/j.cretres.2017.04.011 |
| Image |  |
| Year | 2017 |
| Alt Series | Earth Sciences Sector, Contribution Series 20160319 |
| Publisher | Elsevier BV |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf; html |
| Area | Hokkaido; Mikasa; Pombetsu Valley; Japan |
| Lat/Long WENS | 140.0000 145.0000 45.0000 42.0000 |
| Subjects | paleontology; stratigraphy; Lower Cretaceous; Albian; systematic paleontology; taxonomy; nomenclature; biostratigraphy; fossil morphology; fossil descriptions; fossil zones; fossil assemblages;
paleogeography; Ammonites; Douvilleiceras; Douvilleiceras mammillatum; Douvilleiceras inaequinodum; Douvilleiceras cf. offarcinatum; Douvilleiceras alternans; Trinitoceras; Eodouvilleiceras; Epicheloniceras; Yezo Group; Hikagenosawa Formation;
Shuparogawa Formation; Phanerozoic; Mesozoic; Cretaceous |
| Illustrations | location maps; geoscientific sketch maps; lithologic sections; photographs; schematic representations; sketches; tables; charts |
| Program | Science laboratory network |
| Released | 2017 04 22 |
| Abstract | The early to middle Albian genus Douvilleiceras from the Yezo Group of Hokkaido, Japan, is examined systematically. Five species referred previously to the genus are identified as D. mammillatum
(Schlotheim, 1813), D. inaequinodum (Quenstedt, 1846), D. cf. offarcinatum (White, 1887), D. alternans Casey, 1962, and D. sp. A revision is made of the genus Douvilleiceras, and 40 species described in the literature are reduced to 7 on
morphological criteria, including mode of ribbing, shape of the ventral sulcus, and mode of tuberculation, particularly a distinct difference in the number of tubercles on the primary ribs of the middle growth stage. The genera Trinitoceras and
Eodouvilleiceras, which have been regarded previously as junior synonyms of Douvilleiceras, are morphologically distinguishable from the genus Douvilleiceras and hence considered valid. |
| Summary | (Plain Language Summary, not published)
The authors have described the different species of the extinct fossil genus Douvilleiceras which are found in Cretaceous rocks on the island of
Hokkaido, in the Japanese Islands. These fossil species are about 110 million years old and are very similar to species found in the Cretaceous rocks of western British Columbia, as well as elsewhere around the world. These fossil species are an
important time indicator for the late part of the Early Cretaceous time scale and studying them improves our understanding of this time period of Earth history. |
| GEOSCAN ID | 299643 |
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