Hoplonemertean larvae
NOTE: It is likely that the larvae of many hoplonemerteans (e.g., Emplectonema sp. 1, Paranemertes californica, Poseidonemertes collaris, Gurjanovella littoralis, Tetrastemma bilineatum) start out with just a single pair of eyes, and possibly, develop more pairs before settlement because adult individuals often have many more eyes.
Does your larva have an apical tuft?
Conspicuous apical tuft.
Apical tuft inconspicuous, although possibly present.