Return

HEMICYCLASPIS

This osteostracan was a more powerful swimmer, and could maneuver itself better in water, than either of its bottom-dwelling relatives Tremataspis or Dartmuthia. A dorsal fin stabilized the body, while a pair of scale-covered flaps, like pectoral fins, provided uplift and kept it on course. The corners of the head shield were drawn out into keel-like cutwaters. And the enlarged upper lobe of the tail produced lift at the rear of the body, so keeping the fish's head down while it sucked up food from the seabed. ©1988 Marshall Editions Limited .