Diversity of Chalcidoidea (Hymenoptera) at El Edén Reserve, Mexico

Animal diversity is declining worldwide, and our efforts to document this change are hampered by inaccurate estimates of the true number of species. The number of described (formally named) species has been estimated to be between 1.2–2.2 million (Stork 1988; Grove & Stork 2000), with insects by far the most dominant group (751,012 species according to Arnett 1985). As groups are revised and types reexamined, many of the names proposed are placed as synonyms of other species. This leads to as much as a 25% decrease in our estimates of the number of described species (May 1999), but not, however, in the tremendous number of species that remain to be discovered.