Sexual dimorphism in Nautilus from Palau

  title={Sexual dimorphism in Nautilus from Palau},
  author={W Bruce Saunders and Claude Spinosa},
  pages={349 - 358}
Shells of 375 sexed specimens of Nautilus cf. N. pompilius trapped at 300–700 ft (90–215 m) depth off Mutremdiu Point and Ngemelis Island, Palau, exhibit distinctive dimorphism in shell proportion and overall size. Of 221 mature animals, males have larger shells (mean diameter = 209 mm), a broader aperture (mean maximum width = 99 mm; mean width at apertural salient = 92 mm) and greater weight (mean shell + body weight = 1426 gm). Female shells are smaller (mean diameter = 198 mm), narrower… 

Natural rates of growth and longevity of Nautilus belauensis

Capture-mark-recapture of Nautilus belauensis in Palau shows that this species is shown to live for at least 4 yr beyond maturity, and captured animals' life span may exceed 20 yr.

Whorl Width in the Body Chamber of Ammonites as a Sign of Dimorphism

Examples of dimorphism from the literature and personal studies on faunas from the Trento Plateau (Northern Italy) are given, demonstrating the great importance of the W:D ratio with which dimorphic pairs can be recognized.

Morphologic Variation of Nautilus pompilius from the Philippines and Fiji Islands

Morphologic variation of Nautilus pompilius Linnaeus (Mollusca, Cephalopoda) is described using the two samples from the Tahon Strait, the Philippines and from the water near the Viti Levu Island,

Mature Modifications and Sexual Dimorphism

Most ammonoids display a distinctly different morphology when they are adults or subadults. Depending on the taxon, these mature modifications may comprise changes in coiling, changes in

Nautilus growth and longevity: evidence from marked and recaptured animals.

  • S. Wb
  • Environmental Science
  • 1984
Study of Nautilus belauensis i its natural habitat in Palau, West Caroline Islands, shows that growth is slow and decreases as maturity is approached and that individuals may live at least 4 years beyond maturity.

Nautilus at Risk – Estimating Population Size and Demography of Nautilus pompilius

These results provide the first Nautilid population and density estimates which are essential elements for long-term management of populations via sustainable catch models and provide confidence for their more widespread use to assess efficiently the size and density of exploited and unexploited Nautilus populations worldwide.

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

Live-caught animals from 150–400 m depth off Ambon provide the first morphologic and genetic details on Nautilus pompilius from the type region, including a recently proposed neotype for the type species.

Genetic Variation in the Cephalopod Nautilus belauensis

The moderate levels of genetic variability discovered are discussed in light of the traditional status of Nautilus as a bradytelic living fossil.

Demographic disequilibrium in living nautiloids (Nautilus and Allonautilus): Canary in the coal mines?

Data show that patterns of trap yields and demographic differences between fished and unfished populations in relative age class and sex ratios can indicate disequilibria wrought by fisheries pressure that can render local populations inviable.

An ecomorphospace for the Ammonoidea

An ecomorphospace where life history traits can be tentatively assigned to species of the Ammonoidea is revealed, being one of the ectocochleate cephalopods with best properties for active life (capacity for handling large food items, rather good mobility) and Recent Nautilus has a marginal position.



The reproductive biology of Nautilus pompilius in the Philippines

During the 8 month period, there was no trend apparent in the changes in average size of the ovaries collected; however, oocytes within varied markedly in their maximum weight.

Notes on animal weight, cameral fluids, swimming speed, and color polymorphism of the cephalopod Nautilus pompilius in the Fiji Islands

All newly captured specimens were heavier than seawater, with mean weight in seawater of 1.87 g determined for twenty-five specimens, and average cameral liquid os- molarity was lower than that observed in sampled populations of N. macromphalus from New Caledonia and N. pompilius from the Philippine Islands.

Goniatiten mit Radula und Kieferapparat in der Itararé-Formation von Uruguay

Radula and jaws were found in the livng chamber of eight goniatites from a marine transgression of the Itararé formation of northern Uruguay. The goniatites are preserved in phosphorite concretions

Prodrome d'une monographic des Ammonites

    Dimorphism in Jurassic ammonites, some reflections

    • 1969

    Mature modification and dimorphism in late Paleozoic ammonoids . Pp . 1 0 1 - 1 1 0 and pis . 2 - 5

    • 1969