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"C. magus is characterized by a remarkable conchological divergence between separate populations....Within the same population, C. magus may be either largely uniform or fairly variable in shell morphology."
Manual of Living Conidae (1995) by Röckel, Korn, and Kohn
Aside from its variability, Conus magus ("The Magician's Cone") also is known for a peptide in its cone venom discovered by a young undergraduate student working in the laboratory of Baldomero Olivera. Synthesized and marketed as Prialt (Ziconotide), it is considered a primary alternative (hence the name) to morphine in the management of intractable neuropathic pain. Unlike an opiate receptor, which becomes less efficacious over time, the synthesized form of the omega-conotoxin acts directly on the calcium channel by blocking the synapse from the pain fiber to nerve cells in the spinal cord, thereby inhibiting the transmission of pain—an efficacy that does require, however, the drug being administered intrathecally (directly into the spine).
Prialt is the synthetic analog of only one of approximately one-hundred components in the venom of C. magus. Given that cone snails, which number between 500 and 700 species, produce their own unique set of conotoxins, each numbering between fifty and two-hundred peptide sequences, tens of thousands of possible combinations have evolved, each specific to the animal that is hunted, whether a marine worm, other mollusks, or fish.
The picture of Conus Magus shows some of the variety in the patterning of its shell.
References: Linnaeus: Systema Naturae (1758), 10th ed. (p. 716, no. 276); "Ziconotide for Treatment of Severe Chronic Pain" (2010) by A. Schmidtko, J. Lötsch, R. Freynhagen, and G. Geisslinger, Lancet, 375(9725), 1596-1577; Manual of the Living Conidae (1995) by Dieter Röckel, Werner Korn, and Alan J. Kohn; "Conus Venoms: A Rich Source of Novel Ion Channel-Targeted Peptides" (2004) by Heinrich Terlau and Baldomero M. Olivera, Physiological Reviews, 84(1), 41-68; "Pharmacological Study of the Venom of the Gastropod Conus Magus" (1965) by R. Endean and Joan Izatt, Toxicon, 3(2), 81-93; "Pharmacology of the Venom of the Gastropod Conus Magus" (1974) by R. Endean, P. Gyr, and Glenda Parish, Toxicon, 12(2), 117-129; "The Venom Apparatus of Conus Magus" (1967) by R. Endean and Claudine Duchemin, Toxicon, 4(4), 275-284.
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