Invertebrates: Molluscs – Polyplacophorans (Chitons)

Chitons are, by far, my favorite hitchhikers with their coat of armor (eight plates) and algae rasping ability. 

I only manage to find one about every year though, so they’re a bit hard to come by (they are rarely offered for sale).  The chitons I’ve had have all been nocturnal.  I rarely saw them, but every morning I could tell exactly where they had visited in the aquarium.

Chitons have magnetite teeth (magnetic in some species), according to Bevan Plank’s article, “Animals with Metallic Teeth.”  These teeth are self-sharpening and allow the chitons to make some serious damage to algae-covered rocks.  During the night the chitons would clear a path down to the rock and make short work of the algae film. 

Chitons do not keep solely to the rockwork; they also venture onto the glass.  Use caution in removing a chiton as they have an insane capability to grip by acting like a suction cup. 

I do not know of any successes with reproduction in home aquaria, but that may be due to the short supply (therefore few aquariums with multiple chitons).  I had two chitons come on a coral a few months ago, but they were juveniles (and possibly different species).  Due to their small size (about the size of a grain of rice), I have not seen them since.

Here’s a photo of one out in the wild off the coast of California (rather cold water). 

The Chiton’s ability to clear algae, neat appearance, and rarity make it a great hitchhiker find.

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