Scale Microornamentation of Six Species of Venomous Snakes from China

The scales of six venomous snake species from China were examined for their ultrastructure. Scanning electron microscopy was used to observe the scales, which were peeled off from the middle back of the snakes. The results revealed significant differences in the microdermatoglyphic structure patterns between the two families, Viperidae and Elapidae. Viperidae exhibited a “polygonal” structural unit, while Elapidae displayed arcs, pores, and strips as their basic structure. Additionally, there were notable differences in ultrastructure within each family. In Viperidae, Ovophis makazayazaya had a flat structural unit, Trimeresurus stejnegeri had a mound-like uplift near the center with a flat surrounding, and Protobothrops mucrosquamatus had an overall uplifted structure. In Elapidae, Ophiophagus hannah showed obvious differences in the size and arrangement of arc structures. The intraarc structure of Bungarus multicinctus resembled vertebral bodies, while that of Sinomicrurus peinani was columnar in shape. The ultrastructural characteristics of snake scales generally exhibited essential differences among advanced taxonomic units. However, there were detailed differences among species within the same family or genus. The initial formation of microornamentation features in scales may be related to the snakes’ habitat environment. Species formation through isolation is accompanied by the differentiation of these characteristics, and once species formation occurs, the features remain stable until the next species differentiation. There were instances of similar structures found in species with distant evolutionary relationships. This suggests that the microdermatoglyphic structure has taxonomic significance but may not necessarily have phylogenetic significance.