What does "pycnogonida" mean?

Pycnogonida: A class of marine arthropods in which the body is small and thin, and the eight legs usually very long; -- called also Pantopoda. Note: The abdomen is rudimentary, and the triangular mouth is at the end of a tubular proboscis. Many of them live at great depths in the sea, and the largest of them measure two feet across the extended legs.

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