FIGURE 6 in New Austrognathiidae (Gnathostomulida: Conophoralia) from Hong Kong and Japan: microscopic anatomy, ultrastructure and evolutionary implications

FIGURE 6. Austrognatharia orientis sp. nov.; electronmicrographs of protonephridia (A–E) and the male copulatory organ (F, G). A. Cilium and microvilli with indentation of terminal cell. Arrowheads point to origin of filamentous rods. B. Cross section through terminal cell and canal cell at a plane proximal to the termination of the microvilli of the terminal cell. C. Cross section through terminal cell and canal cell distal to the termination of the microvilli of the terminal cell. Arrows point to ECM. D. Detail of C showing the protonephridial canal and the surrounding six rods of filamentous material. Note that the rods are clearly an intracellular part of the canal cell. E. Section through the nephroporus showing the nephroporus cell and the canal cell. Note the cilium reaching from the protonephridial duct into the nephroporus and the many microvilli of the nephroporus cell. Asterisk marks the cilium of the terminal cell, arrowhead points to centriole of the nephroporus cell. F. Distal part of penis with electron-lucent vesicles. Arrows point to the basal matrix at the base of the penis cells. Note microvilli in the ejaculatory duct. G. Distal, glandular part of male copulatory organ enclosing a mature conulus. Note the numerous electron-dense vesicles in the gland cells. Abbreviations: c conulus, cc canal cell, ep epidermal cell, po nephroporus cell, tc terminal cell. Scale bars: A, D 250 nm; B, C, E 1 µm; F 2 µm; G 5 µm.