Fig. 8 in Comparative analysis of spermiogenesis and sperm ultrastructure in Callichthyidae (Teleostei: Ostariophysi: Siluriformes)

Fig. 8. Spermatozoa of Hoplosternum littorale. a) Spermatozoon in longitudinal section. b and c) Nucleus in cross sections. d) Detail of centriolar arrangement. e to j) Midpiece in longitudinal and transverse sections showing mitochondria, elongated vesicles, and cytoplasmic channel. k) Flagellum in longitudinal section. j-inset) Flagellum in cross section showing classical (9+2) axoneme. (a, b, h) X 17000; (c) X 13800; (d to g) X 23000; (i) X 33600; (j, k) X 31500; (j-inset) X 57500. D: distal centriole; E: electron-dense structure; F: flagellum; N: nucleus; P: proximal centriole; V: vesicles; Asterisk: mitochondria, Arrow: cytoplasmic channel.