Allonautilus: a new genus of living nautiloid cephalopod and its bearing on phylogeny of the Nautilida

@article{Ward1997AllonautilusAN,
  title={Allonautilus: a new genus of living nautiloid cephalopod and its bearing on phylogeny of the Nautilida},
  author={Peter D. Ward and W Bruce Saunders},
  journal={Journal of Paleontology},
  year={1997},
  volume={71},
  pages={1054 - 1064}
}
  • P. Ward, W. Saunders
  • Published 1 November 1997
  • Biology, Environmental Science
  • Journal of Paleontology
Living ectocochliate cephalopods have long been thought to be restricted to a single genus, Nautilus Linnaeus, 1758, comprising five or six extant species. The shells of two species, N. scrobiculatus Lightfoot, 1786, and N. perforatus Conrad, 1847, are quite distinct, but no soft-parts were known until 1984, when N. scrobiculatus was seen alive for the first time. Dissections show that significant anatomical differences exist between N. scrobiculatus and other Nautilus species, including… 

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Systematics of Cephalopods

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Descriptions of Nautilus pompilius Linnaeus, 1758 from the Type Area, Ambon, Molucca Islands, and from Sumbawa - Lombok Islands, Indonesia

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  • Environmental Science, Geography
  • 2000
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The two pairs of gills, which occur in extant nautilids only, are suggested to reflect a minor anatomical modification to improve respiration in low oxygen settings by the duplication of the cephalopod initial single pair of gill structure, and are thus of no taxonomic significance.

Occurrence of a specific dual symbiosis in the excretory organ of geographically distant Nautiloids populations.

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ABBREVIATED CLASSIFICATIoN oF THE PHYLUM MoLLUSCA

  • Biology
olluscs include some of the best-known invertebrates; almost everyone is familiar with snails, clams, slugs, squids, and octopuses. Molluscan shells have been popular since ancient times, and some
...

References

SHOWING 1-10 OF 45 REFERENCES

Genetic divergence and geographic diversification in Nautilus

TLDR
DNA sequence analysis indicates that there are three geographically distinct clades consisting of western Pacific, eastern Australian/Papua-New Guinean, and western Australian/Indonesian forms, and morphologically and genetically distinct species Nautilus scrobiculatus falls outside the three geographically recognized assemblages.

Nautilus : the biology and paleobiology of a living fossil

Nautilus Studies—The First Twenty-Two Centuries -- Nautilus Studies—The First Twenty-Two Centuries -- The Ancestry of the Genus Nautilus -- The Ancestry of the Genus Nautilus -- Nautilus and Its

The role of the environment in the nautilacea

TLDR
The classification of the superfamily Nautilaceae, which includes all post-Triassic nautiloids, rests at present on purely typological criteria, but recent studies have shown that many of these characteristics are related of the mode of life of the animal, and are consequently susceptible to repeated occurrences in different lineages.

Is Nautilus a Living Fossil

  • P. Ward
  • Environmental Science, Geography
  • 1984
The two quotes above are representative of the controversy concerning the age of Nautilus, the last externally shelled cephalopod. If we accept the first age estimate, we would have to include

Ammonoid cephalopods from the Lower Permian of Thailand

The purpose of the present statement is to announce discovery of a well-preserved and potentially diverse Lower Permian ammonoid fauna from south-central Thailand. Previous Thai records of Permian

Devonian ancestors ofNautilus

KurzfassungEin Nautilide aus dem oberen Famenne, welcher teilweise die morphologische und phylogenetische Lücke zwischen dem Givet und dem Tournai füllt, wird unter dem NamenDasbergoceras n. gen.

Rates of Evolution and the Notion of "Living Fossils"

TLDR
The genome is simply a convenient term for the genetic constitution of an individual or species, and thus genomic change introduces the notion of geonomically regulated reproductive incompat­ ibility, and two interrelated aspects of speciation theory are considered.

Life at low oxygen tensions: the behaviour and physiology of Nautilus pompilius and the biology of extinct forms

TLDR
It is argued that a Nautilus -like physiology and behaviour could well have contributed to the success of extinct ectocochleate forms, living in oceans that were, by and large, less well oxygenated than now.

Eine neue tertiäre Molluskenfauna aus dem Indischen Archipel

Die Versteinerungen, welche den Gegenstand der folgenden Untersuchungen bilden, stammen aus Asphaltkalken der Insel Buton (hollandisch Boeton) und befanden sich teils in der Sammlung vom „Dienst van

Geometric analysis of shell coiling; general problems

Among the shells of invertebrates that exhibit spiral growth, differences in form can be expressed by differences in geometric parameters. If three parameters are considered at a time, the spectrum