Conus magus Linnaeus, 1758
Magus cone, 71mm

Conus magus is a common lagoon dwelling cone, where it lives on the interisland reefs and occasional lagoon pinnacles. It usually buries in sand, sometimes beneath rocks, during the day and emerging at night to hunt fish. As a piscivorous species, it has a potentially dangerous venomous sting and should be handled with care. Specimens have been found at depths ranging from about 3 to 30m. The species varies considerably in coloration, from nearly all light cream-colored to sporting various amounts of brown spiral bands or even black streaks arranged more or less in spiral bands. Some specimens can be confused with some forms of Conus circumcisus. As one of the most common fish-eating cone shells, Conus magus has been used extensively in venom studies. As noted in Wikipedia, Ziconotide is a chemical derived from the Conus magus venom that acts as a painkiller with a potency 1000 times that of morphine.

Below you can see the siphon coming out of the narrow anterior end of the aperture. Below that is the mouth, flanked on either side by a short white tentacles with a black eye. Below that is the anterior edge of the foot, which in this species is white with a large black blotch.

Like most cone shells, this species is covered by a brown translucent protein-based periostracum.

They lay their eggs in clusters of whitish capsules glued to the undersides of rocks or Halimeda clumps. Each capsule contains a number of white to light pink eggs.

Looking down into the capsules, you can see the individual eggs as small white balls.


Created 4 July 2009
Updated 16 March 2017

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