Fig. 6.

Epistome myoanatomy and innervation of Stephanella hina. Confocal laser scanning microscopy stacks based on acetylated alpha-tubulin labelling. Volume renderings, projections or optical slices. Acetylated alpha-tubulin in green LUT, f-actin in glow LUT. a Volume rendering of the epistomial musculature from the anal side. Note the lateral epistomial canal muscles. b Maximum projection of the same volume in A showing thin lateral muscle fibres lateral to the epistomial canal muscles. c Optical section through the foregut and the epistome showing individual, smooth muscle fibres crossing. d Lateral rendering showing epistomial musculature and dense lateral ciliation on their proximo-lateral side. e Volume rendering of the epistomial musculature. f Innervation of the epistome. A thin plexus extends directly from the cerebral ganglion. Abbreviations: a – anus, afr – abfrontal muscle root, cg – cerebral ganglion, crl – ciliary ridge laterally of the epistome, ecl – epistome canal muscles, ep – epistome, epi – epistome innervation, epm – epistome musculature, lb. – lophophoral base, mo – mouth opening, ph – pharynx, phc – pharynx ciliation, rm. – retractor muscle, ti – tentacle innervation, tm – tentacle muscles, ts – tentacle sheath