Showing papers by "Ellen E. Strong published in 2021"
National Museum of Natural History1, Smithsonian Environmental Research Center2, Duke University3, Northeastern University4, Illinois Wesleyan University5, Tohoku University6, California State University, Monterey Bay7, Monterey Bay Aquarium Research Institute8, University of Maine9, Whitney Laboratory for Marine Bioscience10, University of Bologna11
TL;DR: It is argued that a multi-marker approach combined with taxonomic expertise to develop a curated, vouchered, local barcode database increases taxon detection with metabarcoding, and its potential as a tool for zooplankton biodiversity surveys is argued.
Abstract:
The performance of DNA metabarcoding approaches for characterizing biodiversity can be influenced by multiple factors. Here, we used morphological assessment of taxa in zooplankton samples to develop a large barcode database and to assess the congruence of taxonomic identification with metabarcoding under different conditions. We analysed taxonomic assignment of metabarcoded samples using two genetic markers (COI, 18S V1–2), two types of clustering into molecular operational taxonomic units (OTUs, ZOTUs), and three methods for taxonomic assignment (RDP Classifier, BLASTn to GenBank, BLASTn to a local barcode database). The local database includes 1042 COI and 1108 18S (SSU) barcode sequences, and we added new high-quality sequences to GenBank for both markers, including 109 contributions at the species level. The number of phyla detected and the number of taxa identified to phylum varied between a genetic marker and among the three methods used for taxonomic assignments. Blasting the metabarcodes to the local database generated multiple unique contributions to identify OTUs and ZOTUs. We argue that a multi-marker approach combined with taxonomic expertise to develop a curated, vouchered, local barcode database increases taxon detection with metabarcoding, and its potential as a tool for zooplankton biodiversity surveys.
16 citations
TL;DR: In this paper, the authors report seven new stromboid mitogenomes obtained from transcriptomic and genomic data, with taxonomic representation from each Recent strombid family, including the first mitogenome for Aporrhaidae, Rostellariidae, Seraphsidae and Struthiolariidae.
6 citations
TL;DR: Pseudomohniarogerclarkisp. nov. is established for a new species from the Aleutian Islands characterized by its narrowly turreted shell and distinctive multicuspid rachidian as mentioned in this paper.
Abstract: Mohniakurilana Dall, 1913 was described more than 100 years ago from deep waters off the Kuril Islands and remains exceedingly rare in museum collections. Originally placed in the carnivorous neogastropod family Buccinidae, fragmentary soft parts from the type lot and from several specimens belonging to allied species collected in the Aleutian Islands in the 1990s have allowed anatomical investigations for the first time. These have revealed the presence of a paucispiral operculum with an eccentric nucleus, foot with a deep propodial pedal gland and metapodial pedal gland, taenioglossate radula, short acrembolic proboscis, well-developed mid-esophageal gland, glandular prostate, and the absence of a penis; the nervous system is epiathroid with a long supra-esophageal connective and numerous statoconia in the statocysts. Analysis of the gut contents revealed abundant halichondriid sponge spicules. This evidence indicates a placement in the Triphoroidea, a diverse superfamily of specialized spongivores. Mohniakurilana is transferred to the Newtoniellidae and placed in the new genus Pseudomohniagen. nov.Pseudomohniarogerclarkisp. nov. is established for a new species from the Aleutian Islands characterized by its narrowly turreted shell and distinctive multicuspid rachidian. A lectotype is designated for Mohniakurilana.
TL;DR: Viviparids have experienced population collapse 30‐ to 50‐fold more severe than that seen in haplochromine cichlids from the region, and population declines began 100K years earlier, prior to the last glacial maximum (~15,000–18,000 years ago).
Abstract: Understanding the interplay between ecological and population genetic processes through space and time is a central goal of landscape genetics. However, most studies that place diversification dynamics in an ecological context have focused on vertebrates, leaving a significant gap in our understanding of the effects of ecosystem change on community composition and demography of invertebrates. In the East African Rift System, cichlid fishes have emerged as a powerful model system for understanding adaptive radiation (Kornfield & Smith, 2000), but few studies have examined diversification of other taxa. In this issue of Molecular Ecology, Van Bocxlaer et al. (2020) use landscape genetic approaches to model historical demography and diversification of viviparid gastropods in the Lake Victoria ecoregion. They show that while phylogeographic patterns are similar between the two, viviparids and cichlids have responded in very different ways to the climatic upheavals of the Pleistocene and that their responses have been at least partially asynchronous. Viviparids have experienced population collapse 30- to 50-fold more severe than that seen in haplochromine cichlids from the region, and population declines began 100K years earlier, prior to the last glacial maximum (~15,000-18,000 years ago). Their results reveal a new facet to the profound and lasting impacts of Pleistocene climate change on the modern fauna of the Lake Victoria ecoregion and its ability to respond to current human-mediated stressors.