Pierson's Puppeteers

Pierson's Puppeteers are a fictional alien species in Larry Niven's Ringworld series ("Known World universe").

Puppeteers reproduce using three "genders": a non-sentient female who carries the fetus, an egg-producing sex with an ovipositor; and a sperm-producing sex with a penile organ. The egg- and sperm-producing sexes refer to themselves as "he", and refer to the non-sentient host gender as "she", female, also described as a "drone". Technically the non-sentient host is a "cousin" species which is fertile with itself, and breeds more drones.