Short-beaked echidna (Tachyglossus aculeatus).
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The spiny-back eel, Notacanthus sexspinis, is a deep-sea spiny eel of the genus Notacanthus, found in all the southern hemisphere oceans, in depths between 500 and 1,000 m. Their length is up to 60 cm. The spiny-back eel is a deep-bodied scaleless eel-like fish with a blunt rounded snout overhanging a small mouth. The dorsal fin has been reduced to 6 or 7 short sharp spines widely separated on the back but the anal fin is long, extending from midway along the body to the tip of the tail.
These fish are a pallid off-white colour faintly tinged with pink, and are black inside the mouth and lips.