Abstract: Salamanders have evolved functions of attaching to a variety of surfaces under wet conditions, but racial diversity may cause a diference in attachment behaviors and epidermal characteristics. The sticking and climbing abilities of the Chinese Fire Belly Newt (CFBN), Chinese Warts Triton (CWT), Spotless Stout Newt (SSN), and Chinese Giant Salamander (CGS) on various surfaces were investigated and compared in terms of epidermal morphology, body size, and wettability. The results indicate that the spotless stout newt has an excellent ability for wet attachment, compared to other salamanders under a certain contact case, resulting from its lower mass/body surface area and more visible epidermal structures. Supplementation with moderate water is benefcial for salamander attachment, and the surface roughness in the food case also promotes the wet attachment. The CFBN has the most hydrophilic epidermis among the samples, where the water droplet quickly spreads over, presenting a completely wetting case. This study ofers a comprehensive understanding of the wet attachments and the epidermal characteristics of salamanders, which is meaningful for the application of bioinspired adhesives.

Key words: Wet attachment, Salamander, Epidermal structure, Wettability