The number of described species on the planet is about 1.9 million, with ca. 17,000 new species described annually, mostly from the tropics. However, taxonomy is usually described as a science in crisis, lacking manpower and funding, a politically acknowledged problem known as the Taxonomic Impediment. Using data from the Fauna Europaea database and the Zoological Record, we show that contrary to general belief, developed and heavily-studied parts of the world are important reservoirs of unknown species. In Europe, new species of multicellular terrestrial and freshwater animals are being discovered and named at an unprecedented rate: since the 1950s, more than 770 new species are on average described each year from Europe, which add to the 125,000 terrestrial and freshwater multicellular species already known in this region. There is no sign of having reached a plateau that would allow for the assessment of the magnitude of European biodiversity. More remarkably, over 60% of these new species are described by non-professional taxonomists. Amateurs are recognized as an essential part of the workforce in ecology and astronomy, but the magnitude of non-professional taxonomist contributions to alpha-taxonomy has not been fully realized until now. Our results stress the importance of developing a system that better supports and guides this formidable workforce, as we seek to overcome the Taxonomic Impediment and speed up the process of describing the planetary biodiversity before it is too late.

We investigated the interacting impacts of urban landscape and gardening practices on the species richness and total abundance of communities of common butterfly communities across France, using data from a nationwide monitoring scheme. We show that urbanization has a strong negative impact on butterfly richness and abundance but that at a local scale, such impact could be mitigated by gardening practices favoring nectar offer. We found few interactions among these landscape and local scale effects, indicating that butterfly‐friendly gardening practices are efficient whatever the level of surrounding urbanization. We further highlight that species being the most negatively affected by urbanization are the most sensitive to gardening practices: Garden management can thus partly counterbalance the deleterious effect of urbanization for butterfly communities. This holds a strong message for park managers and private gardeners, as gardens may act as potential refuge for butterflies when the overall landscape is largely unsuitable.

Faunistic surveys are fundamental in the conservation of land mollusks, particularly as a means of achieving accurate es-timates of species richness and levels of extinction of endangered taxa. The family Endodontidae comprises one of the most diverse groups of indigenous land snails of Pacific Islands. Due to anthropogenic degradation of their habitats, most members of the family are now extinct or severely endangered. In Rurutu, French Polynesia, 11 species of Endodontidae were previously described (10 endemics), but only 1 is known to have been extant during the first half of the 20th Century. Extensive collections made in Rurutu in 2003 recovered only empty shells of these 11 species, as well as of an additional 8 endemic species of endodontids not known to previous investigators: Australdonta oheatora sp. nov., A. anneae sp. nov., A. sibleti sp. nov., A. florencei sp. nov., A. pakalolo sp. nov., A. teaae sp. nov., Minidonta boucheti sp. nov. and M. bieleri sp. nov. The radiation of endodontids in Rurutu was thus much larger than previously envisaged. However, we hypothesize that all species of the family are now extinct in the island.