The hair band (in Japanese "Hachimaki")

Kanehira(Acheilognathus rhombeus) is one of the species which spawn in autumn.

Bitterlings present remarkable secondary sex characteristic in the spawning season.
All male bitterlings have very beautiful nupitial coloration.It seems that there are strong competition among males struggling for limited spawning resources,freshwater mussels.
It is not too much to say that male Kanehira is the most beautiful species among such beautiful bitterlings.

When I was a graduate school student, I talked about the beauty of male Kanehira with my professor.
In the conversation I emphasised the beauty of it's green and pink body color.
One the other hand, my professor said "I think the best point is it'  Hachimaki (in English "Hair band")"
"Hachimaki?"I repied.
So, I couldn't understand what he said at that time.

After several years, when I took their under water photos and watched pictures,I understood.
I see.
White and silver running through their forehed seems the strong will to the next generation.