This EOSC in practice story was developed within the Cos4cloud project and targets a very wide user base as it is addressed to any researchers, teachers, students, companies, institutions and, more generally, anyone interested in knowing, studying or analysing biodiversity information. The story presents Cos4Bio, a co-designed, interoperable and open-source service that integrates biodiversity observations from multiple citizen observatories in one place, allowing experts to save time in the species identification process and get access to an enormous number of biodiversity observations. This resource is available on the EOSC Portal Catalogue and Marketplace The full list of EOSC in practice stories is available here