Albert CardonaI didn't think anything an acoel is or can do would surprise me at this point (I do have a PhD in the embryonic development of a somewhat related animal group, the flatworms), but here we are:
"they investigated reproductive behaviour and discovered a new mode of egg-laying: H. miamia lays eggs through its mouth. The eggs are deposited in communal clutches, and individuals assess environmental conditions to decide whether – and when – to lay eggs, indicating a more complex neural control of reproductive activity."