This pteropod (Limacina helicina) has taken a beating from being pulled through a trawl net: you can see the broken edges of its shell. An abundant species with black flesh, each of these sea butterflies are the size of a large grain of sand. In certain conditions they “bloom” and, when fish eat too many, the pteropod’s black coloring stains the fishes’ guts black.
Read more: http://www.smithsonianmag.com/science-nature/amazing-sea-butterflies-are-the-oceans-canary-in-the-coal-mine-61813612/#E8xJ8KAc3FqQtJbp.99
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