Nanopositioning is one of the most intriguing challenges in nanoelectronics and photonics. As the optoelectronic circuit components become more and more complex, the importance of nano- positioning becomes critical. For example, in single-mode fiber telecommunications it is easy to show that an alignment deviation as small as a few tens of nanometers can yield to 50 percent of loss performance. Diatoms are unicellular plants occurring in almost every aquatic environment. Their main morphological character is the frustule, a silica cell wall that consists of two valves, encasing the protoplasm, joined together by a girdle. The girdle is composed of a series of silica bands (copulae) linked together along their margins. In several diatom species, the first girdle bands (valvocopulae), which associate the valves with the rest of the girdle, appear different in shape and bring specific nanostructures devoted to facilitate …