Conus (Lividoconus) muriculatus sugillatus 31.4 & C. muriculatus: Conoidea: Conidae

[JackSullivan]

A very nice shell for the P.I. Very similar to Conus (Lividoconus) floridulus for having a deep blue siphonal canal but this feature seems to be lacking in other snails in this subgenus. Blue pigmentation in these snails is a bit of a puzzle, especially as it appears to be concentrated only in the siphonal canal.

The last 2 pix are of a 29 mm C. muriculatus I just purchased to highlight the blue siphonal canal in these species.

In mollusks the formation of blue pigments has been associated with the indigoid pigment mixture called Tyrian Purple but this reddish-blue pigment is only formed by external chemical processing of colorless precursor molecules found in internal mollusk glands. Another blue mollusk biochemical is the respiratory pigment hemocyanin, a protein which forms complexes with copper ions that are blue in the presence of oxygen & colorless otherwise. Oxygenated hemocyanin in the hemolymph vessels around the bases of these cones could explain the observed blue pigmentation. Hemolymph vessels so close to the outside of the shell could have an environmental function such as heat exchange with the surrounding sea water for thermoregulation. Still a third possible contributor to blue cone snail pigmentation is biliverdin, a tetrapyrrole that is dark green in its pure, isolated form but which can appear blue in crystalline calcium carbonate matrices, such as the bird shells of the emu & the familiar robin.

[JackSullivan]

A very nice shell for the P.I. Very similar to Conus (Lividoconus) floridulus for having a deep blue siphonal canal but this feature seems to be lacking in other snails in this subgenus. Blue pigmentation in these snails is a bit of a puzzle, especially as it appears to be concentrated only in the siphonal canal.

The last 2 pix are of a 29 mm C. muriculatus I just purchased to highlight the blue siphonal canal in these species.

In mollusks the formation of blue pigments has been associated with the indigoid pigment mixture called Tyrian Purple but this reddish-blue pigment is only formed by external chemical processing of colorless precursor molecules found in internal mollusk glands. Another blue mollusk biochemical is the respiratory pigment hemocyanin, a protein which forms complexes with copper ions that are blue in the presence of oxygen & colorless otherwise. Oxygenated hemocyanin in the hemolymph vessels around the bases of these cones could explain the observed blue pigmentation. Hemolymph vessels so close to the outside of the shell could have an environmental function such as heat exchange with the surrounding sea water for thermoregulation. Still a third possible contributor to blue cone snail pigmentation is biliverdin, a tetrapyrrole that is dark green in its pure, isolated form but which can appear blue in crystalline calcium carbonate matrices, such as the bird shells of the emu & the familiar robin.

I bought another example of C. muriculatus from a seller in Hawaii. As you can see from the pix, the siphonal canal is also colored blue.