Tail Forms Of Betta splendens Siamese Fighting Fish A descriptoin of the tail forms of Betta splendens Siamese Fighting fish. Tail Forms of Betta splendens The Siamese Fighting Fish To complement the many colour strains of Betta splendens, there are also around 12 recognised variations of caudal tail fin forms. As with the Guppy Poecilia reticulata, Betta splendens carry a diverse range of