Crusty Nautilus

Taxobox
name = Crusty Nautilus

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image_caption = "Allonautilus scrobiculatus" shell with periostracum removed
image_width = 200px
regnum = Animalia
phylum = Mollusca
classis = Cephalopoda
ordo = Nautilida
familia = Nautilidae
genus = "Allonautilus"
species = "A. scrobiculatus"
binomial = "Allonautilus scrobiculatus"
binomial_authority = (Lightfoot, 1786)
synonyms =
*"Nautilus scrobiculatus"
Lightfoot, 1786
*?"Nautilus umbilicatus"
Linne, 1758

The Crusty Nautilus ("Allonautilus scrobiculatus") is a species of nautilus native to the waters around New Guinea, specifically New Britain and Milne Bay, and the Solomon Islands. "A. scrobiculatus" is instantly recognisable by the large open umbilicus, which is around 20% of the shell diameter at its widest point. This species, along with the closely related "A. perforatus", were originally placed in the genus "Nautilus", but have recently been given their own genus on account of significant morphological differences. The most obvious are features of the shell, including crease and an encrusting layer (periostracum) that covers most of the shell. Gills and reproductive structures also differ significantly from members of the genus "Nautilus". The shell is usually up to around 18 cm in diameter, although the largest specimen ever recorded measured 215 mm. [cite book | author = Pisor, D. L. | year = 2005 | title = Registry of World Record Size Shells | edition = 4th edition | publisher = Snail's Pace Productions and ConchBooks | pages = p. 93]

References

* Norman, M. 2000. "Cephalopods: A World Guide". Hackenheim, ConchBooks, p. 31.

External links