Abstract: Rattan is a typical tropical climbing plant that uses flagella to climb supports to grow. A comprehensive understanding of the anatomic structure and micromechanics of rattan flagella might inspire more research on biomimetic climbing materials. Here, the structure and micromechanical properties of flagella in calamus simplicifolius were examined by Micro-Computed Tomography (Micro-CT) and nanoindentation techniques, respectively. The results showed that the rachis of the flagella mainly comprised vascular bundles surrounded by basic tissues, which had a gradient density decreasing from outsides to insides. The prickles are derived from the epidermis or the epidermis and cortical tissue of the flagellum, which do not possess vascular tissue. The entire tip of the prickle was composed almost of fibrous cells. The indentation modulus of elasticity of the prickle was 17.03 GPa, which was 17.93% higher in comparison with the rachis. The hardness of the prickle was 539.27 MPa and was slightly higher than that of the rachis. The results indicated that the discrepancy of micromechanical strengths in different parts of flagella reflects on their unique roles in the process of climbing.

Key words: Calamus simplicifolius , · Micromechanical properties , · Structure , · Flagellum , · Biomaterials