Fig. 6

Light (a) and transmission electron (b-i) micrographs of sample sections of epidermis in adult worms of Quasitetrastemma stimpsoni. a Panoramic view of the longitudinal section of the anterior end of the worm with an apical pit (arrowhead). b Panoramic view of longitudinal section of extremely anterior end. c Multiciliated cells (asterisks) located between ducts of the frontal gland. d Basal region of the multiciliated cells (asterisk) of the apical pit attached to the extracellular matrix (arrows). e Perinuclear cytoplasm of multiciliated cells of the apical pit. f Ciliary rootlets comprising horizontal (hr) and axial (ar) rootlet of multiciliated cell of the apical pit. g Ciliary rootlets comprising two horizontal (hr) and one axial (ar) rootlet of multiciliated cells of the epidermis. h Bodies of mucoid cells (asterisks). i Periphery of the secretory portion of the frontal gland with nuclei of granular gland cells (asterisks). Abbreviations: app–apical pit; ar–axial rootlet; d–ducts of frontal glands; dl–dorsal lobe of frontal gland; dmc–ducts of mucoid cells; ep–epidermis; hr–horizontal rootlet; pr–proboscis; rs–rhynchostome; tf–tonofilaments; vl–ventral lobe of frontal gland