Sea Urchins

Unknown Sea Urchin 1 at 5000 ft Axial Seamount

Sea Urchins belong to Class Echinoidea (Phylum Echinodermata).

Unknown Sea Urchin 1

Unknown Sea Urchin 1This is easily the most common sea urchin found on Axial.  It is often observed hiding among the lobed basalt lavas.  Its size is only 10-15 cm in diameter.





Spiny Sea Urchin (Tromikosoma panamense)

Spiny Sea UrchinThe Tromikosoma panamense sea urchin has only been observed on a few occasions, and is not common at Axial. This specimen was seen at the base of Axial Seamount. The T. panamense has a hard armored shell, consisting of small plates covered in spines.