Name: 6-arm pluteus larva stage
ECAO ID: 0000490
Definition: "The 6-arm pluteus larva is mainly characterized morphologically by the presence, on the ventral side, of six arms, and by the development, on the anterior midline of the esophagus, of the dorsal arch. The larva has indeed extended on the ventral side two additional posterodorsal arms and has developed on the anterior side an additional skeletal element called the dorsal arch. In addition, at the basis of the postoral and posterodorsal arms, four small patches of ciliary band have by now cut off and migrated toward the apex, forming four patches of ciliated structures called the epaulettes (one posterior and one anterior pair). The nervous system of the larva has also become more complex with cell bodies and axons being present all along the arms and for the latter as well throughout the apex. The left and right coelomic pouches have continued to elongate on each side of the digestive tract. As a note this stage is relatively fleeting."
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