Fig. 4 in Comparative analysis of spermiogenesis and sperm ultrastructure in Callichthyidae (Teleostei: Ostariophysi: Siluriformes)

Fig. 4. Spermatozoa of Corydoras aeneus. a) Longitudinal section. b and c) Nucleus in cross sections. d) Detail of centriolar arrangement. e to j) Midpiece longitudinal and transverse sections showing mitochondria, vesicles, membranous compartment, and electron-dense circular structure. k and l) Flagellum in longitudinal sections. m and n) Flagellum in cross sections. (a, d) X 17000; (b) X 13800; (c) X 15750; (e, h, k, l) X 23000; (f) X 20400; (g) 44100; (i, j) X 31500; (m) X 47250; (n) X 57500. B: basal body; D: distal centriole; E: electron-dense structure; F: flagellum; N: nucleus; P: proximal centriole; V: vesicles; Asterisk: mitochondria, Arrow: cytoplasmic channel; Arrowhead: lateral membranous compartment; Double arrowhead: electron-dense material between the centrioles; Lozenge: electron-dense circular structure.