Figure 4 from: Yanwirsal H, Bartsch P, Kirschbaum F (2017) Reproduction and development of the asian bronze featherback Notopterus notopterus (Pallas, 1769) (Osteoglossiformes, Notopteridae) in captivity. Zoosystematics and Evolution 93(2): 299-324. https://doi.org/10.3897/zse.93.13341

Figure 4 - Elements of the courtship behaviour in Notopterus notopterus.(a) Around the spawning site the male touched the female's abdomen with his mouth; (b) the pair resting together on the bottom; (c and d) sequences of gravel removal/nesting site preparation by the male.