Despite claims of an insect decline worldwide, our understanding of extinction risk in insects is incomplete. Using bionomic data of all odonate (603 dragonflies and damselflies) North American species, we assessed (i) regional extinction risk and whether this is related to local extirpation; (ii) whether these two patterns are similar altitudinally and latitudinally; and (iii) the areas of conservation concern. We used geographic range size as a predictor of regional extinction risk and body size, thermal limits and habitat association as predictors of local extirpation. We found that (i) greater regional extinction risk is related to narrow thermal limits, lotic habitat use and large body size (this in damselflies but not dragonflies); (ii) southern species are more climate tolerant but with more limited geographic range size than northern species; and (iii) two priority areas for odonate conservation are the cold temperate to sub-boreal northeastern USA and the transversal neo-volcanic system. Our approach can be used to estimate insect extinction risk as it compensates for the lack of abundance data.

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1. Analysis of geographic patterns of extinction must be accompanied by knowledge of biodiversity patterns. Such analysis is not yet available in insects given three shortfalls. First, knowledge of insect species' distribution is poor. Second, insect inventories have taxonomic, geographical, temporal and habitat biases. Third, the accelerated loss of insect species likely surpasses the rate at which the authors are discovering new species.2. The authors have examined the state of the art of knowledge of the geographical distribution of insect extinction risk and diversity, as well as their relation with human footprint.3. Insect records are highly scattered. Geographically, inventories are incomplete worldwide, except for some areas in Europe. Although the description of new insect species has increased in the last 40 years, this is biased towards lepidopterans and coleopterans. Comparably, IUCN-listed species has also increased in the last 40 years, yet with biases towards odonates and lepidopterans. Likewise, aquatic species have been more intensively sampled and considered by the IUCN than terrestrial species. Of high priority are some pristine areas but with few insect records, whereas the east coast of the United States, Europe and Japan raise concerns given that the human footprint exceeded the species richness of insects registered.