Copyright J. Anderson www.nudibranch.org/Scottish%20Nudibranchs/aplysia-punctat…
Simultaneous hermaphrodite, but distant spacing and positioning of male and female organs prevents mutual interchange of gametes between a side-to-side couple. Acting-male climbs astride acting-female from behind and with anterior of foot firmly grips mantle and shell (via foramen) of acting-female. Penis of acting-male, engorged by blood and extruded by eversion of internal penis sheath, curves backwards and downwards to be inserted into vaginal part of other’s common genital aperture.

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