D N A L i b r a r y o f L i f e , r e s e a r c h a r t i c l eurn:lsid:zoobank

New genetic diagnostic approaches have greatly aided efforts to document global biodiversity and improve biosecurity. This is especially true for organismal groups in which species diversity has been underestimated historically due to difficulties associated with sampling, the lack of clear morphological characteristics, and/or limited availability of taxonomic expertise. Among these methods, DNA sequence barcoding (also known as “DNA barcoding”) and by extension, meta‐barcoding for biological communities, has emerged as one of the most frequently utilized methods for DNA‐based species identifications. Unfortunately, the use of DNA barcoding is limited by the availability of complete reference libraries (i.e., a collection of DNA sequences from morphologically identified species), and by the fact that the vast majority of species do not have sequences present in reference databases. Such conditions are critical especially in tropical locations that are simultaneously biodiversity rich and suffer from a lack of exploration and DNA characterization by trained taxonomic specialists. To facilitate efforts to document biodiversity in regions lacking complete reference libraries, we developed a novel statistical approach that categorizes unidentified species as being either likely native or likely nonnative based solely on measures of nucleotide diversity. We demonstrate the utility of this approach by categorizing a large sample of specimens of terrestrial insects and spiders (collected as part of the Moorea BioCode project) using a generalized linear mixed model (GLMM). Using a training data set of known endemic (n = 45) and known introduced species (n = 102), we then estimated the likely native/nonnative status for 4,663 specimens representing an estimated 1,288 species (412 identified species), including both those specimens that were either unidentified or whose endemic/introduced status was uncertain. Using this approach, we were able to increase the number of categorized specimens by a factor of 4.4 (from 794 to 3,497), and the number of categorized species by a factor of 4.8 from (147 to 707) at a rate much greater than chance (77.6% accuracy). The study identifies phylogenetic signatures of both native and nonnative species and suggests several practical applications for this approach including monitoring biodiversity and facilitating biosecurity.

Island plant–pollinator networks are typically simpler than their continental counterparts and this can make them less resilient to disturbance from exotic species. French Polynesia has a very low diversity of bees, but their status as either native or introduced species has been largely speculative. We combine previous studies with new DNA sequence data to show that 11 bee species have now been recorded for French Polynesia. Haplotype variation at the ‘barcode’ region of the mitochondrial gene cytochrome c oxidase subunit I (COI) for four of these species, Ceratina dentipes Freise, Xylocopa sonorina Smith, Braunsapis puangensis (Cockerell) and Amegilla pulchra (Smith), indicates that they all represent very recent introductions. Apis mellifera Linnaeus was a purposefully introduced species, and four megachilid species probably arrived due to human‐aided dispersal through maritime activities in the Pacific. The two remaining bee species, an unidentified partial specimen of a halictid bee and the colletid bee Hylaeus (P.) tuamotuensis Michener, are collectively known from only four specimens collected in the 1930s and their provenance is uncertain. French Polynesia therefore comprises a region where recently introduced bee species greatly overwhelm any possible native bee fauna. These introductions are likely to have major ecosystem impacts, including disruptions of existing plant–pollinator networks and facilitating the spread of weedy plant species, as well as positive impacts for agriculture. Future biosecurity initiatives need to consider these potential impacts and the likely routes of dispersal to effectively control any further unintended introductions.

An annotated checklist for the terrestrial and freshwater arthropods of French Polynesia is presented. Compiled with the help of 48 experts and based on published records, it comprises 3025 valid species names belonging to the classes of Hexapoda Blainville, 1816 (2556 species), Chelicerata Heymons, 1901 (36 7 species), Myriapoda Latreille, 1802 (22 species) and Crustacea Pennant, 1777 (80 species). Reported are 1841 taxa from the Society Islands, followed by the Marquesas Islands with 1198 taxa, the Austral Islands with 609 taxa, the Tuamotu Islands with 231 taxa and the Gambier Islands with 186 taxa. The specificity of this fauna and the analysis of each class and order are discussed. The level of endemism is particularly high, 61% of the known species, with non-native species representing 13% of the overall species count. The threats to the native fauna and flora of French Polynesia and particularly to endemic insect species are detailed. RÉSUMÉListe de référence des arthropodes terrestres et d'eau douce de Polynésie française (Chelicerata; Myriapoda; Crustacea; Hexapoda). Une liste de référence annotée des arthropodes terrestres et d'eau douce de Polynésie française est présentée. Compilée avec l'aide de 48 experts et basée sur les ouvrages publiés, elle comprend 3 025 espèces valides appartenant aux classes des Hexapoda Blainville, 1816 (2 556 espèces), Chelicerata Heymons, 1901 (36 7 espèces), Myriapoda Latreille, 1802 (22 espèces) et Crustacea Pennant, 1777 (80 espèces). Des îles de la Société sont répertoriés 1 841 taxons, suivis des Îles Marquises avec 1 198 taxons, des Îles Australes avec 609 taxons, des Tuamotu avec 231 taxons et enfin des Gambier avec 186 taxons. La spécificité de cette faune et l'analyse de chaque classe et ordre sont discutées. Le niveau d'endémisme est particulièrement élevé, représentant 61% des espèces connues, les espèces introduites représentant 13% du nombre total d'espèces. Les menaces pesant sur la faune et la flore native de Polynésie française et en particulier sur les insectes endémiques sont détaillées.

No abstract