Fig. 5

Schemes of innervation of tentacles and the lophophore in Hemithiris psittacea. a Organization of the outer tentacles. b Organization of the inner tentacles. c A portion of the lophophore brachium with different nerve tracts. d The scheme of the lophophore nervous system: tentacles, brachial fold, and paired outer radial nerves are not shown. Abbreviations: af – abfrontal zone; afn – abfrontal tentacular nerve; an – accessory brachial nerve; cn – cross nerve; ecm – extracellular matrix; f – frontal zone; fn – frontal tentacular nerve; itn – intertentacular nerve; laf – laterofrontal zone; lafn – lateroabfrontal tentacular nerve; lf – laterofrontal zone; lfn – laterofrontal tentacular nerve; ln – lower brachial nerve; mn – main brachial nerve; orn – paired outer radial nerves; sa – second accessory nerve; tc – tentacular coelom; tv – tentacular blood vessel