Overview
- A peer-reviewed paper published June 29, 2026 in PNAS reports a conservative global estimate of 14 million to 20 million insect species based on new empirical data and statistical modelling.
- Researchers analyzed more than 1.6 million specimens from Costa Rica’s Área de Conservación Guanacaste and detected roughly 54,000 species using DNA barcodes as species markers.
- The team focused on Microgastrinae parasitoid wasps collected by three methods, used that group to estimate about 333,000 insect species in the ACG, and then scaled that figure to the world using geographic ratios from trees, mammals, amphibians and moths.
- The authors note large uncertainties in scaling but stress the result is conservative and that most insect species—only about 1.2 million have been formally described—are likely small, rare, ecologically specialized and easily missed by single sampling methods.
- The study combines high-throughput barcoding with statistical estimators to set a new baseline for biodiversity work, highlight the taxonomic bottleneck that limits species description, and underscore that many undescribed insects could already be declining and need urgent monitoring and conservation.