Sexual dimorphism in Nautilus from Palau

@article{Saunders1978SexualDI,
  title={Sexual dimorphism in Nautilus from Palau},
  author={W Bruce Saunders and Claude Spinosa},
  journal={Paleobiology},
  year={1978},
  volume={4},
  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… 

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