One of the most crucial questions of twenty-first century systematic biology deals with the determination of the real number of living species currently sharing the Earth with us (Cracraft 2002); answers vary widely, but commonly range between 3 and 100 million (see, for example, Stork 1997 or May 2002 and references therein). However, in terms of completeness and correctness, our current inventory of living species is certainly unsatisfactory (Dubois 2003), as the total number of species described so far is known to correspond to only a very small fraction of the Earth's biodiversity. Indeed, large numbers of species remain to be discovered, primarily insects, small invertebrates and, above all, microorganisms (Chevalier et al. 1997). On the other hand, this gap of knowledge regarding the magnitude of the Earth's biodiversity limits our capacity to properly manage the world's biotic resources and conserve biological diversity in this socalled Century of Extinctions (Dubois 2003): the current biodiversity crisis is wiping out a significant fraction of living species at an alarming rate and, sadly, an unknown number of species is being forever lost before being discovered, described, and named. Likewise, conservation priorities are clearly constrained by our limited knowledge of the total biodiversity (Dubois 2003, Scotland et al. 2003). Assuming that 1.5-2 million eukaryote species have been collected, studied and named from Linnaeus' work until now (Cracraft 2002, May 2002, Mace et al. 2005), and that the total figure might lie somewhere between 10-20 million, some authors (Wilson 2003b, 2005) consider feasible to discover, describe and name, in a limited time span, all eukaryote species roaming the Earth. To allow the completion of this Encyclopedia of Life, as it has been termed (Wilson 2003b; see also Wilson 2006), it is imperative to overcome the so-called taxonomie impediment (Dubois 2003, Wheeler et al. 2004, de Carvalho et al. 2005, Evenhuis 2007) which is currently obstructing much needed advancement in sound management of known species (Crisci 2006) and discovery of unknown ones (de Carvalho et al. 2007, Evenhuis 2007). In short, the taxonomic impediment results from (i) deep knowledge gaps in our taxonomie system, (ii) the lack of expert taxonomists and curators to handle the enormous, overwhelming task of classifying the unknown biodiversity and (iii) the impact of these two limitations on our ability to conserve, use and share the benefits of biological diversity. Although it is also questionable, for this paper I will assume that we can not enjoy and protect something if we don't know what is out there to enjoy and protect (Evenhuis 2007). On this matter, and based on his own museum experience, Wilson (2004) reckons that if we double the current number of practising taxonomists (at the moment, it is estimated to be ca. 6,000-7,000 taxonomists) (Schnack & López 2003, Wilson 2004), and provide each of them with the help of several technical assistants and novel technologies (e.g., genomic maps, web publication, etc.), the global biodiversity survey could be completed within a single human generation, i.e. 25 years. Nonetheless, other authors (May 2004) have expressed doubts about the feasibility of this vast project, particularly taking into account the present rate of new species description, i.e., around 10,000 species per year considering the synonymy load (May 2002, 2004, Dubois 2008). Copyright © 2008 - Magnolia Press.
