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Glass, J. R.

Publications and source records attributed to Glass, J. R..

3 recordsLinked to original sources

Genome of a Giant (Trevally): Caranx ignobilis

Caranx ignobilis, commonly known as the kingfish or giant trevally, is a large, reef-associated apex predator. It is a prized sportfish, targeted heavily throughout its tropical and subtropical range in the Indian and Pacific Oceans, and it has drawn significant interest in aquaculture due to an unusual tolerance for freshwater. In this study, we present a high-quality nuclear genome assembly of a C. ignobilis individual from Hawaiian waters, which have recently been shown to host a genetically distinct population. The assembly has a contig NG50 of 7.3Mbp and scaffold NG50 of 46.3Mbp. Twenty-five of the 203 scaffolds contain 90% of the genome. We also present the raw Pacific Biosciences continuous long-reads from which the assembly was created. A Hi-C dataset (Dovetail Genomics Omni-C) and Illumina-based RNA-seq from eight tissues are also presented; the latter of which can be particularly useful for annotation and studies of freshwater tolerance. Overall, this genome assembly and supporting data is a valuable tool for ecological and comparative genomics studies of kingfish and other carangoid fishes.

genomics↗

Genome Assembly of the Roundjaw Bonefish (Albula glossodonta), a Vulnerable Circumtropical Sportfish

BackgroundBonefishes are cryptic species indiscriminately targeted by subsistence and recreational fisheries worldwide. The roundjaw bonefish, Albula glossodonta is the most widespread bonefish species in the Indo-Pacific and is listed as vulnerable to extinction by the IUCNs Red List due to anthropogenic activities. Whole-genome datasets allow for improved population and species delimitation, which - prior to this study - were lacking for Albula species. ResultsWe generated a high-quality genome assembly of an A. glossodonta individual from Hawai i, USA. The assembled contigs had an NG50 of 4.75 Mbp and a maximum length of 28.2 Mbp. Scaffolding yielded an NG50 of 14.49 Mbp, with the longest scaffold reaching 42.29 Mbp. Half the genome was contained in 20 scaffolds. The genome was annotated with 28.3 K protein-coding genes. We then analyzed 66 A. glossodonta individuals and 38,355 SNP loci to evaluate population genetic connectivity between six atolls in Seychelles and Mauritius in the Western Indian Ocean. We observed genetic homogeneity between atolls in Seychelles and evidence of reduced gene flow between Seychelles and Mauritius. The South Equatorial Current could be one mechanism limiting gene flow of A. glossodonta populations between Seychelles and Mauritius. ConclusionsQuantifying the spatial population structure of widespread fishery species such as bonefishes is necessary for effective transboundary management and conservation. This population genomic dataset mapped to a high-quality genome assembly allowed us to discern shallow population structure in a widespread species in the Western Indian Ocean. The genome assembly will be useful for addressing the taxonomic uncertainties of bonefishes globally.

genomics↗

Prolonged morphological expansion of spiny-rayed fishes following the end-Cretaceous

Spiny-rayed fishes (Acanthomorpha) dominate modern marine habitats and comprise more than a quarter of all living vertebrate species1-3. It is believed that this dominance resulted from explosive lineage and phenotypic diversification coincident with the Cretaceous-Paleogene (K-Pg) mass-extinction event4. It remains unclear, however, if living acanthomorph diversity is the result of a punctuated burst or gradual accumulation of diversity following the K-Pg. We assess these hypotheses with a time-calibrated phylogeny inferred using ultraconserved elements from a sampling of species that represent over 91% of all acanthomorph families, as well as an extensive body shape dataset of extant species. Our results indicate that several million years after the end-Cretaceous, acanthomorphs underwent a prolonged and significant expansion of morphological disparity primarily driven by changes in body elongation, and that acanthomorph lineages containing the bulk of the living species diversity originated throughout the Cenozoic. These acanthomorph lineages radiated into distinct regions of morphospace and retained their iconic phenotypes, including a large group of laterally compressed reef fishes, fast-swimming open-ocean predators, bottom-dwelling flatfishes, seahorses, and pufferfishes. The evolutionary success of spiny-rayed fishes is the culmination of a post K-Pg adaptive radiation in which rates of lineage diversification were decoupled from periods of high phenotypic disparity.

evolutionary biology↗