Browsing by Author "Pauls, Steffen U."

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    DNA barcode data confirm new species and reveal cryptic diversity in Chilean Smicridea (Smicridea) (Trichoptera:Hydropsychidae)
    (The North American Benthological Society, 2010) Pauls, Steffen U.; Blahnik, Roger J.; Zhou, Xin; Wardwell, C. Taylor; Holzenthal, Ralph W.
    Mitochondrial deoxyribonucleic acid (mtDNA) sequence data have been both heralded and scrutinized for their ability or lack thereof to discriminate among species for identification (DNA barcoding) or description (DNA taxonomy). Few studies have systematically examined the ability of mtDNA from the DNA barcode region (658 base pair fragment of the 59 terminus of the mitochondrial cytochrome c oxidase I gene) to distinguish species based on range-wide sampling of specimens from closely related species. Here we examined the utility of DNA barcode data for delimiting species, associating life stages, and as a potential genetic marker for phylogeographic studies by analyzing a rangewide sample of closely related Chilean representatives of the caddisfly genus Smicridea subgenus Smicridea. Our data revealed the existence of 7 deeply diverged, previously unrecognized lineages and confirmed the existence of 2 new species: Smicridea (S.) patinae, new species and Smicridea (S.) lourditae, new species. Based on our current taxonomic evaluation, we considered the other 5 lineages to be cryptic species. The DNA barcode data proved useful in delimiting species within Chilean Smicridea (Smicridea) and were suitable for life-stage associations. The data also contained sufficient intraspecific variation to make the DNA barcode a candidate locus for widespread application in phylogeographic studies.
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    Taxonomy and systematics: contributions to benthology and J-NABS
    (University of Chicago Press, 2010) Holzenthal, Ralph W.; Robertson, Desiree R.; Pauls, Steffen U.; Mendez, Patina K.
    Systematics, or taxonomy, is the study of the diversity of life on Earth. Its goals are to discover and describe new biological diversity and to understand its evolutionary and biogeographic origins and relationships. Here we review the contributions to the field of systematics and taxonomy published over the last 25 y in J-NABS and its predecessor Freshwater Invertebrate Biology (FIB). We examined a total of 64 studies that we considered to be largely taxonomic in nature. We classified these studies into 2 major categories: morphological (e.g., descriptive taxonomy, taxonomic revisions) and molecular (e.g., deoxyribonucleic acid [DNA] barcoding, population genetics). We examined studies in 5-y increments for J-NABS. We also studied the period 1982 to 1985, during which FIB was published. On average, 12 taxonomic studies were published within each 5-y period. Molecular studies first appeared in 1986 and have slowly increased, reaching their greatest number within the last 5 y. Studies also were classified by their individual attributes. Morphological studies were, by far, the most common, but studies also included molecular data, biological information, distributional data, keys, and biogeographical analyses. Most studies included .1 of these attributes. Overall, the role of J-NABS in the development of benthic taxonomy has been minimal in terms of number of publications, but as part of the nexus of taxomonic literature, all contributions have been important to the discipline. We discuss these contributions and their impact on the following subject areas: taxonomy and revisionary systematics, phylogenetic and molecular systematics, taxonomic resources, taxonomic resolution, conservation and taxonomy, professional training, taxonomic certification, and graduate education. We also give an overview of new developments in the taxonomists’ toolbox. These developments include DNA barcoding, online taxonomic resources, digital identification keys, cybertaxonomy, and modern museum collections and resources.
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    The Trichoptera barcode initiative: a strategy for generating a species-level Tree of Life
    (The Royal Society Publishing, 2016) Zhou, Xin; Frandsen, Paul B.; Holzenthal, Ralph W.; Beet, Clare R.; Bennett, Kristi R.; Blahnik, Roger J.; Bonada, Nu´ria; Cartwright, David; Chuluunbat, Suvdtsetseg; Cocks, Graeme V.; Collins, Gemma E.; deWaard, Jeremy; Dean, John; Flint, Oliver S. Jr; Hausmann, Axel; Hendrich, Lars; Hess, Monika; Hogg, Ian D.; Kondratieff, Boris C.; Malicky, Hans; Milton, Megan A.; Morinie`re, Je´roˆme; Morse, John C.; Ngera Mwangi, Francois; Pauls, Steffen U.; Razo Gonzalez, Marı´a; Rinne, Aki; Robinson, Jason L.; Salokannel, Juha; Shackleton, Michael; Smith, Brian; Stamatakis, Alexandros; StClair, Ros; Thomas, Jessica A.; Zamora-Munoz, Carmen; Ziesmann, Tanja; Kjer, Karl M.
    DNA barcoding was intended as a means to provide species-level identifications through associating DNA sequences from unknown specimens to those from curated reference specimens. Although barcodes were not designed for phylogenetics, they can be beneficial to the completion of the Tree of Life. The barcode database for Trichoptera is relatively comprehensive, with data from every family, approximately two-thirds of the genera, and one-third of the described species. Most Trichoptera, as with most of life’s species, have never been subjected to any formal phylogenetic analysis. Here, we present a phylogeny with over 16 000 unique haplotypes as a working hypothesis that can be updated as our estimates improve. We suggest a strategy of implementing constrained tree searches, which allow larger datasets to dictate the backbone phylogeny, while the barcode data fill out the tips of the tree. We also discuss how this phylogeny could be used to focus taxonomic attention on ambiguous species boundaries and hidden biodiversity. We suggest that systematists continue to differentiate between ‘Barcode Index Numbers’ (BINs) and ‘species’ that have been formally described. Each has utility, but they are not synonyms. We highlight examples of integrative taxonomy, using both barcodes and morphology for species description. This article is part of the themed issue ‘From DNA barcodes to biomes’.