Merpersons

[Koen G]

I suspect they were aiming for "unblemished": pale skin, blond hair, youthful appearance. 

Regarding the larger scene, I think there are some Pharisees among the onlookers. This is probably a reference to Jonah's typological meaning: his resurrection from the fish foreshadows that of Christ. Apparently Christ was even explicit about this in the NT, promising the Pharisees "the sign of Jonah", which is his resurrection. Learned figures watching Jonah's resurrection would have reminded the audience of the (more relevant) NT verse.