Campanian (Late Cretaceous) nautiloids from Sakhalin
first biostratigraphically well dated nautiloids from Sakhalin, which show close affinities to nautiloid faunas from Japan (Hokkaido), the two areas having formed part of a southerly palaeobiogeographical subprovince of the North Pacific Province. Possible relationships between shell form/ornament a...
| Main Authors: | , , |
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| Format: | Text |
| Language: | English |
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| Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.612.7916 http://app.pan.pl/archive/published/app48/app48-481.pdf |
| Summary: | first biostratigraphically well dated nautiloids from Sakhalin, which show close affinities to nautiloid faunas from Japan (Hokkaido), the two areas having formed part of a southerly palaeobiogeographical subprovince of the North Pacific Province. Possible relationships between shell form/ornament and preferred habitats of Late Cretaceous nautiloids are discussed. Coarsely ribbed (“cymatoceratid”), depressed nautiloids seem to predominate in nearshore environments. This may be regarded as an adaptive response to increasing predation pressure by durophages, especially in shallow water set− tings, which may have triggered the development of defensive morphologies (i.e., ornamented, predation−resistant shells) in Cretaceous shallow−water nautiloids. |
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