zygosis
From ZooTerms (Dictionary of Invertebrate Zoology)
zygosis (noun; Greek zygosis, a joining): 1. Conjugation.
2. (Arthropoda: Insecta) In coccids, the median lobes of the pygidium that are united basally by internal sclerotization.
3. (Mollusca: Gastropoda) A neural connection between the supraintestinal ganglion and the pleural ganglion on the left side or between the subintestinal ganglion and the pleural ganglion on the right side
See also: orthoneury.
