A couple of urchins here. A familiar and quite common Red Pencil Urchin, and a Diadema Savignyi Urchin. The latter one is rare in Hawaii and looks a lot like the Long-spined Urchin, but is distinguished by the striking blue lines on its test.
Diadema Savignyi Urchin
Graham's Island 
Specky shot! The contrast in colour and form is fabulous.
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I like the different varieties of urchins. There’s a remarkable range of appearance.
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A couple of beauties with the rare one really looking sharp. đŸ˜‰
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Most urchins are sharp and best not stepped on!
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