Combien y a-t-il d'espèces de coléoptères en Guyane ? Une première analyse du référentiel TAXREF

This paper analyzes the Coleoptera part of the first global checklist of insects from French Guiana, up to the end of 2013, published online in the French species database TAXREF (http://inpn.mnhn.fr). We describe the level of knowledge by family, the pace of description and compare it with other insect Orders. We also focus on characterizing the patterns in the taxonomical work currently concerning this beetles fauna.
Excluding erroneous or dubious records, 5 830 species of Coleoptera are reported in 1852 genera belonging to 71 families. Currently at least 28% of the species are only known from French Guiana or from the Guiana shield region. Since Linné, the average rate of description has been of 23 species per year, but it has been increasing recently, reaching 84 species on average these last five years. Based on a sample of recent taxonomic and faunistic articles covering 625 added species for French Guiana, 47% came from new country records and 53% from the description of new species. The rate of faunistic progress (new species or new records) is of about 150 species per year (84 new species + 66 new country records) during the last five years. More than 65% of these faunal novelties came from non-professional entomologists and 73% of the holotypes of new species were collected by amateur entomologists. A rough extrapolation of the potential number of species using two independent methods yields a likely estimate of 28 000 to 29 000 species (overall between 20 000 and 39 000). Therefore, between 70 and 80% of the species remains to be recorded and, in a best-case scenario, at least 100 years would be needed to achieve a complete biotic survey. Although no family is exhaustively inventoried, the most popular ones are the best studied (Longhorns, Scarabs and Tiger beetles). The most in need of study are the largest families that have fewer taxonomists focusing on them (e.g. Curculionidae, Chrysomelidae and Staphylinidae) and the numerous small families which received no particular attention. These results and the fundamental role played by non-professional entomologists in collecting and describing species are discussed to explain why, unlike the general worldwide trend, there is no decline in beetles taxonomy concerning French Guiana.