Fig. 6

TEM micrographs of surface ultrastructure of Dibothriocephalus latus plerocercoids. Uncinate (arrowhead) and coniform (sinuous arrow) spinitriches and solitary distributed long capilliform filitriches (straight arrow); tegument composed of a distal cytoplasm containing numerous electron-dense bodies and vesicles (a, b). Cross-sections through the two types of microtriches. Note the structure of the coniform spinitriches cap (c). The distal cytoplasm with electron-dense bodies, vesicles and the secretory duct after discharge of the secretory granules (d). Underlying perikariya. The basal lamina delimited the distal cytoplasm from the underlying longitudinal and circular muscle layers. The lamina reticularis is filled with anchoring fibrils, oriented perpendicularly to the basal membrane (e). Longitudinal section through a non-ciliated receptor. Note the presence of four dense collars, basal body, striated rootlets and a bundle of microtubules (f). Abbreviations: AF, anchoring fibrils; BA, base; BP, baseplate; BB, basal body; BL, basal lamina; CO, collars; CP, cap; D, desmosomes; DB, dense bodies; DC, distal cytoplasm; LM, longitudinal muscles; LR, lamina reticularis; M, microtubules; NF, nerve fibre; NSG, neurosecretory granules; RT, striated rootlets; SD, secretory duct; V, vacuoles