The Collaborative International Dictionary of English v.0.48:

Synapticula \Syn`ap*tic"u*la\, n.; pl. Synapticulae. [NL.,
   dim. from Gr. ? fastened together.] (Zool.)
   One of numerous calcareous processes which extend between,
   and unite, the adjacent septa of certain corals, especially
   of the fungian corals.
   [1913 Webster]