Found during an artificial fertilization experiment. We do not know if it is the result of abnormal development or if the larva was reproducing asexually.

Aboral region (normal position).

Ova.

Arm growing on an unusual site.

Aboral surface.

Accelerated 25x.

Larval skeleton seen through polarized light.

Early stage with two arms showing cells with pigmented granules in the epithelium.

Four-arm stage.

Anus on the juvenile aboral surface (red curved structure).

Embryos during early cellular divisions.

Lateral view. Detail of the lantern of Aristotle under the peristomial membrane (where mouth will open).

Larva with four pairs of arms.

Aboral surface (opposite to mouth).

Aboral surface (opposite to mouth).

Stage with four pairs of arms.

Larva with two pairs of aarms and early development of postero-dorsal arms on the body sides.

After artificial fertilization and raising embryos in the laboratory, blastulae hatch from the vitelline membrane and begin to swim. Development occurs in the water column from gastrulation to pluteus larva stage until metamorphosis.

Larva with three pairs of arms and a wide mouth.