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1. Some golf courses start off as half-size, 9-hole courses and, if successful, expand in area to full-size courses, thus converting more land to highly managed greenspace. We investigated carabid beetle assemblages in three established and newly created suburban golf courses in Helsinki, southern Finland.2. Beetles were collected from similar habitat types on established courses, newly created courses and nearby reference areas.3. Seventy-one carabid beetle species were collected and the beetle assemblages were dominated by open habitat and generalist species.4. Assemblages differed considerably between the three golf courses studied and between the habitat types sampled, but not between course development stages (established vs. newly created) or reference areas.5. We argue that some carabid beetle species in the urban landscape in Helsinki are resilient and capable of rapidly colonising these modified environments.6. Under current management regimes, these golf courses in Helsinki, Finland, do not host carabid beetles of conservation concern, yet are rich in generalist and open habitat species.

To associate specimens identified by molecular characters to other biological knowledge, we need reference sequences annotated by Linnaean taxonomy. In this paper, we 1) report the creation of a comprehensive reference library of DNA barcodes for the arthropods of an entire country (Finland), 2) publish this library, and 3) deliver a new identification tool based on this resource. The reference library contains mtDNA COI barcodes for 11,275 (43%) of 26,437 arthropod species known from Finland, including 10,811 (45%) of 23,956 insect species. To quantify the improvement in identification accuracy enabled by the current reference library, we ran 1,000 Finnish insect and spider species through the Barcode of Life Data system (BOLD) identification engine. Of these, 91% were correctly assigned to a unique species when compared to the new reference library alone, 85% were correctly identified when compared to BOLD with the new material included, and 75% with the new material excluded. To capitalize on this resource, we used the new reference material to train a probabilistic taxonomic assignment tool, FinPROTAX, scoring high success. For the full-length barcode region, the accuracy of taxonomic assignments at the level of classes, orders, families, subfamilies, tribes, genera, and species reached 99.9%, 99.9%, 99.8%, 99.7%, 99.4%, 96.8%, and 88.5%, respectively. The FinBOL arthropod reference library and FinPROTAX are available through the Finnish Biodiversity Information Facility (www.laji.fi). Overall, the FinBOL investment represents a massive capacity-transfer from the taxonomic community of Finland to all sectors of society.