Haplophrentis' length ranges from 2 mm to 3 cm. It existed on the seabed in a sessile mode of life. The animal used the Helens, the two appendages on either side of the anterior part of the organism, to move slowly on the top of the soft mud feeding on organic material. The Helens provided the creature with balance, preventing it from rolling over in currents.
Pencil and carbon dust on paper
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