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Related to nautiloid: Nautiloidea


Any of various marine cephalopod mollusks formerly classified in the subclass Nautiloidea, including the nautiluses and numerous extinct species known only from fossils.

[From New Latin Nautiloīdea, former subclass name : Latin nautilus, nautilus; see nautilus + Greek -oeidēs, -oid.]

nau′ti·loid adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Animals) any mollusc of the Nautiloidea, a group of cephalopods that includes the pearly nautilus and many extinct forms
(Animals) of, relating to, or belonging to the Nautiloidea
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
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All modern cephalopods are carnivorous predators or scavengers, and before big fish evolved, nautiloids (nautilus relatives) would have been among the major predators in the seas--some nautiloid shells from the Ordovician period measured up to three metres in length.
On the other hand, Jennifer Nouri was wowed to learn that a smooth black rock with a stunning white imprint - originally found in Morocco - turns out to be a 400 million-year-old orthocone nautiloid fossil.
Orthocone nautiloid orientations in Arenig and Llanvirn limestones of Oland, Sweden.
The fossils being referred to are orthocone nautiloids, Rayonnoceras sp., that occur in the top ten feet or so of the Whitmore Wash Member of the Redwall Limestone in Nautiloid Canyon and elsewhere in the Grand Canyon region (Fig.
-- Two nautiloid species, Cimomia ozani new species and Eutrephoceras dekayi (Morton), are described from the Campanian Ozan Formation of the Taylor Group in northeast Texas.
Apart from Dawsonoceras and the Silurian coiled-shell nautiloid Peismoceras Hyatt, no shell colouration was documented in any other species with highly elaborated sculpture.
A very peculiar specimen of a nautiloid phragmocone was found close to the root-bearing surface (Figs 1B, 2E).
At Early Paleocene the transgression of sea emerged which deposited the Sangiali Group like carbonate shallow marine limestone and shale (fossil bearing like bivalves nautiloids and gastropods) of Sangiali Formation deltaic siliciclastic Rakhi Gaj Formation and coral reef deposits of Dungan Limestone.
Shell organic inclusions have also been used to make dietary comparisons between modern and fossil nautiloids (Kashiyama et al.