This article describes how cloud computing and the convergence toward "Everything as a service" have encouraged the proliferation of services ready for use. These facilities have increased the requests of the companies for the development of the applications. In this context, where the reusability is needed, cloud service composition techniques are widely used. However, traditional centralized service composition techniques are not sufficient to address the needs of applications in highly dynamic and open environments. Early attempts for service composition models in decentralized environments have been proposed, but they are limited by their ability to adapt when deploying in highly dynamic and open environments. In this paper, the authors use Stigmergic-based self-organization mechanisms inspired from nature to model the decentralized service interactions and handle service composition in highly dynamic and open environments.