Cyanocharax alburnus (Hensel, 1870) MCP, 1950

Baicere-Silva, Clarianna Martins, Ferreira, Katiane M., Malabarba, Luiz R., Benine, Ricardo C. & Quagio-Grassiotto, Irani, 2011, Spermatic characteristics and sperm evolution on the subfamily Stevardiinae (Ostariophysi: Characiformes: Characidae), Neotropical Ichthyology 9 (2), pp. 377-392 : 381

Cyanocharax alburnus ( Fig. 9 A-G)

In the spermatozoon of Cyanocharax alburnus , the ovoid nucleus measures 1.7  m in the longitudinal axis and 1.4  m in the transverse axis. The surrounding strip of cytoplasm has no organelles ( Fig. 9 A-B). Nuclear rotation toward the flagellar axis was about 70 degrees ( Fig. 9 A-B). The midpiece has a conical shape, measures about 0.9  m in length and contains some slightly elongated mitochondria ( Fig. 9 C-G). The endomembrane system is composed of interconnected vesicles of different sizes (9A-G).

Figures

Fig. 9. Spermatozoa of Cyanocharax alburnus. A-C: Longitudinal sections of spermatozoa. Note the lateral position of the nucleus (n) in relation to the flagellar axis, the eccentric position of the double nuclear fossa (double arrow), the midpiece and the cytoplasmic canal (*) containing the initial segment of the flagellum (f). D-G: Cross sections through the middle of the nucleus and at different levels of the strongly asymmetric midpiece exposing the lateral position of the centriole (c), cytoplasmic canal (*) and of the flagellum (f), the distribution of the few long mitochondria (m) accumulated in larger portion of the midpiece, a possible endomembrane system and a few vesicles peripherally distributed (v).