Hāʻukeʻuke kaupali (Helmet Urchin), Colobocentrotus atratus
I know, I was a little mean and flipped him over...
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Hāʻukeʻuke kaupali (Helmet Urchin), Colobocentrotus atratus
I know, I was a little mean and flipped him over...
Helmet Urchin by Ken-ichi on Flickr.
Adaptations of the amazing Shingle Urchin
The Shingle urchin, Colobocentrotus atrata (Echinometridae), has a peculiar limpet-life morphology, unique among the regular echinoids.
The aboral spines of Colobocentrotus atrata (on the opposite side to the mouth) are extremely reduced, forming a smooth pavement or plates, and the adoral part (situated near the mouth) is surrounded by a basal skirt of flattened spines. These two features improve the adhesive capacities of the animal and are adaptations to life in areas of extreme wave exposure throughout the Indo West Pacific where this sea urchin lives.
[Source]
Photo credit: Shingle urchin in Pu’uhonua o Honaunau National Historical Park, Hawaii (the big island), Hawaii | ©Marlin Harms
Helmet Urchin by Ken-ichi on Flickr.