Figure 6. Transmission electron micrographs of proboscidial monociliated sensory cells of palaeonemertean species. A, Carinina yushini, longitudinal section through a group of sensory cells (asterisks). B, Carinina yushini, transverse section of the receptor process of a sensory cell. C, Carinina yushini, longitudinal section through the globular ciliary tip of a sensory cell. D, Carinina yushini, longitudinal section of a dendrite within the apicolateral junctions (black arrowheads) of a sensory cell. Bundles of microvillar filaments (white arrowheads) are terminated at the cytoplasmic membrane. E, Carinina yushini, transverse section of the proximal region of the dendrite of a sensory cell. Centrally located axial rootlets (asterisk) are surrounded by bundles of microvillar filaments (mf). F, Carinina yushini, transverse section of a distal region of the dendrite of a sensory cell. Arrowheads point to axial rootlets. G, Tubulanus punctatus, longitudinal section of a sensory cell with axial rootlets (white arrowheads). The filament bundles (black arrowheads) of the microvilli extending into the dendrite and terminating into the cytoplasmic membrane (back arrow) below apicolateral junctions

Published as part of Magarlamov, Timur Yu & Chernyshev, Alexei V, 2022, Proboscis sensory cells in Nemertea: comparative morphology and phylogenetic implications, pp. 453-478 in Zoological Journal of the Linnean Society 196 (1) on page 463, DOI: 10.1093/zoolinnean/zlab106, http://zenodo.org/record/7031331