Tlaquanaru 060

Two Trirhynchimaera tauroceratos males engage in the species' characteristic "jousting ritual," where two individuals swim toward each other, head-on, with the intent of swimming past the other to slash the rival with the prominent cheek spines. Less courageous individuals make a perpendicular turn before contact, and swim away.
A pineapple fish, Ananapoply acanthops, swims away in order to avoid becoming a casualty in the duel.