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Abstract Characterization of species diversity of zooplankton is key to understanding, assessing, and predicting the function and future of pelagic ecosystems throughout the global ocean. The marine zooplankton assemblage, including only metazoans, is highly diverse and taxonomically complex, with an estimated ~28,000 species of 41 major taxonomic groups. This review provides a comprehensive summary of DNA sequences for the barcode region of mitochondrial cytochrome oxidase I (COI) for identified specimens. The foundation of this summary is the MetaZooGene Barcode Atlas and Database (MZGdb), a new open-access data and metadata portal that is linked to NCBI GenBank and BOLD data repositories. The MZGdb provides enhanced quality control and tools for assembling COI reference sequence databases that are specific to selected taxonomic groups and/or ocean regions, with associated metadata (e.g., collection georeferencing, verification of species identification, molecular protocols), and tools for statistical analysis, mapping, and visualization. To date, over 150,000 COI sequences for ~ 5600 described species of marine metazoan plankton (including holo- and meroplankton) are available via the MZGdb portal. This review uses the MZGdb as a resource for summaries of COI barcode data and metadata for important taxonomic groups of marine zooplankton and selected regions, including the North Atlantic, Arctic, North Pacific, and Southern Oceans. The MZGdb is designed to provide a foundation for analysis of species diversity of marine zooplankton based on DNA barcoding and metabarcoding for assessment of marine ecosystems and rapid detection of the impacts of climate change.
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Expanded phylogeny of Nomadinae (Hymenoptera: Apidae) with integration of UCE and DNA barcode sequence data
Abstract The apid subfamily Nomadinae is the oldest and most diverse clade of brood parasitic bees. Through the incorporation of data from a variety of sources, we generated the most detailed and taxonomically complete phylogeny of this group to date. Despite differing amounts of genetic data available for different species, the tree topology largely matched with expected relationships based on previous findings, with 95% of barcode-only taxa placed in taxonomically consistent positions and all tribes recovered as monophyletic. We further carried out divergence time estimation to investigate the evolutionary history of Nomadinae and place the phylogeny along the geological time scale, recovering an estimated age of 99 Ma for the group. Testing for the effect of barcode-only taxa on estimated dates indicated that ages for deep nodes were robust, though the inclusion of such taxa with limited sequence data tended to push shallower nodes towards older dates. Though this approach may not be appropriate for all applications, the potential for integration of cytochrome oxidase DNA barcode sequences with modern phylogenomic (ultraconserved element) sequence data is an encouraging indication that the wealth of previously published data available through sequence repositories retains the capacity to be informative to future phylogenetic studies.
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- Award ID(s):
- 2127744
- PAR ID:
- 10591152
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Insect Systematics and Diversity
- Volume:
- 9
- Issue:
- 3
- ISSN:
- 2399-3421
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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