Fig. 19

Neuromuscular details of the lophophore of Lophopodella carteri, stained for f-actin and against acetylated-α-tubulin. A, B Oral view of tentacle bases showing the intertentacular nerve origin (A) and muscle bases within the tentacles. The abfrontal muscle bases include at least 4 median transversal bands. C–F Details of the tentacle innervation, show a main radial nerve from which the laterofrontal (C), lateroabfrontal (D) neurite bundles and abfrontal neurite bundles (E) branch off and innervate one half of a tentacle. Abfrontal, very thin neurites ascent into the intertentacular membrane (F, arrows) Alternating with the radial nerves and therefore congruent with the tentacle muscles, a mediofrontal neurite bundle ascends individually and originates from the circumoral nerve ring (C, D). The pharyngeal plexus is associated with the proximal side of the circumoral nerve ring. Neighbouring mediofrontal neurite bundles are connected via lateral nerves (D). G, H Muscular (G) and neuronal (H) details of the lophophoral arms showing the tentacle muscles associated with the lophophore arm muscles and radial nerves emanating from the ganglionic horns. afm abfrontal muscle, afmb abfrontal muscle base, afn abfrontal tentacle neurite bundle, arn additional radial nerve, ci cilia, con circumoral nerve ring, drn distal radial nerve, em epistome musculature, fm frontal muscle, gh ganglionic horns, lam lophophore arm musculature, lan lateroabfrontal tentacle neurite bundle, lfn laterofrontal tentacle neurite bundle, ln lateral nerves, mfn mediofrontal nerve, mtm median transversal muscle, phm pharynx musculature, pp pharyngeal plexus, rm retractor muscle, rn radial nerve