Echinoida, pluteus larva, undet., length 700 µm, Lanzarote 3.2022. 0:37 min. In the taxon Echinodermata the pluteus larva occurs in Ophiurida and Echinoida. In the latter the “arms” of the larvae are directed upwards in a small angel. These “arms” are stabilized by a skeleton of calcite rods, shining colourful in polarized light. The skeleton may be developed divers with many “arms”.