The Cranchiidae are a family of squid commonly known as “glass squid” which live in oceans around the world. The squid are of no interest to commercial fisheries (yet) and a great deal about this family remains completely unknown. Most of the 60 known species of cranchiidae are small and inconspicuous–indeed the majority are transparent and thus nearly invisible. However the largest known mollusk, the colossal squid (Mesonychoteuthis hamiltoni), is part of the family, (so it might be wise not to antagonize them on the playground).
Glass squid are notable for having stubby swollen-looking bodies and short arms except for one long pair of hunting tentacles. The majority of glass squid have bioluminescent organs which they use to hunt, to communicate and to disguise the faint shadows cast by their transparent bodies (predators of the deep can see even the faintest shadows cast by the dim light from the surface). The cranchiid squids themselves sport a variety of interesting and complex eyes which range from giant circular eyes to stalked eyes to telescoping eyes. This little gallery shows how delicate, diverse, and beautiful (and how utterly alien) these squid can be.
Juvenile cranchiid squid are part of the plankton and live near the surface where they hunt microscopic prey while trying to avoid thousands of sorts of predators. As they mature, they change shape and descend to deeper waters—indeed some species become practically benthic and can be found more than 2 kilometeres under the ocean. Glass squid move up and down the water column by means of a fluid filled chamber which contains an ammonia solution (which maybe explains why they are not on the human menu yet).
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January 8, 2015 at 11:38 AM
The Chaos Realm
Amazing. Loving these fabulous posts…!
January 8, 2015 at 11:34 PM
Wayne
Don’t thank me! Thank the squid…hmm, okay, go ahead and thank me 🙂
November 5, 2015 at 10:59 PM
Richard Portman
Teuthowenia megalops, Cranchia scabra! Pure poetry. You have a great blog, found it today. Thanks and best to you and yours.
November 10, 2015 at 12:57 PM
Wayne
Thanks so much, Richard. I wish the poetry were mine, but it is from the Greeks, the mollusk taxonomists, and the deep oceans!