Non-professional taxonomists have been responsible for describing more than half of the animal species discovered in Europe from 1998 to 2007 (see also Nature 467, 788; 2010). The extraordinary current rate of description of new species makes Europe an unexpected frontier for biodiversity exploration.
The Fauna Europaea database (http://www.faunaeur.org), released in 2004, lists more than 125,000 European species of multicellular terrestrial and freshwater animals. More than 700 new species are described each year in Europe — four times the rate of two centuries ago. However, we have not yet reached saturation in the inventory of European fauna, and we cannot accurately estimate the total number of species living in the continent's ecosystems.
The unprecedented rate of species description has depended heavily on the scientific contribution of unpaid scientists (non-professional and retired professional taxonomists). More attention should be given to ways of enhancing this formidable workforce.
There is an urgent need for an effective policy-supported business plan to complete the biodiversity inventory at European and national levels, preferably targeting species-rich and less-charismatic groups such as mites, rove beetles, micro-wasps and nematodes. Amateurs could be readily integrated into such a framework of defined and coordinated objectives.
The future of amateur taxonomy also depends on incorporating molecular techniques, either through formal training or through collaboration between molecular-oriented professionals and morphology-oriented citizen scientists.