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Compared to traditional morphological identification, DNA barcoding--molecular identification based on sequencing of a segment of mitochondrial cytochrome c oxidase subunit I (COI)--provides a shortcut to authenticating chelonian identifications. Here, we selected 63 government-seized chelonian specimens deposited at Taipei Zoo for DNA barcoding analysis. DNA barcoding and subsequent phylogenetic analysis successfully authenticated 36 chelonian species, including five that are listed in CITES Appendix I. Approximately 90% (57/63) of the specimens were successfully authenticated by our molecular approach, but lack or error of BOLD reference sequences, biological processes such as hybridization, and uncertain species delimitation all reduced the accuracy of DNA barcoding. To increase the accuracy of DNA barcoding, Taipei Zoo will continue to enrich the BOLD database and also establish a genetic database, to include additional genetic markers, by using government-seized chelonian specimens. A fast and accurate method to authenticate seized samples could assist law enforcement agencies to prosecute criminals and restrict illegal exploitation of wild chelonian resources. Key words: COI, turtle, tortoise, terrapin, BOLD. Lorsque comparé à des méthodes traditionnelles d'identification morphologique, le codage à barres de l'ADN--une identification moléculaire fondée sur le séquençage d'un segment du gène codant pour la sous-unité I de la cytochrome c oxydase (COI) mitochondriale--fournit un raccourci pour l'authentification de l'identification de spécimens de chéloniens. Dans ce travail, les auteurs ont choisi 63 spécimens de chéloniens saisis par le gouvernement et déposés au Zoo de Taipei pour analyse par codage à barres. Le codage à barres et l'analyse phylogénétique qui s'en est suivie a permis d'authentifier 36 espèces de chéloniens, dont cinq qui sont sur la liste de l'annexe I du CITES. Environ 90% (57/63) des spécimens ont été authentifiés avec succès par l'approche moléculaire, mais l'absence de séquences de référence BOLD ou des erreurs au sein de celles-ci, des processus biologiques comme l'hybridation ou encore une délimitation incertaine de l'espèce ont tous réduit la performance du codage à barres. Afin d'augmenter la justesse du codage à barres, le Zoo de Taipei va continuer à enrichir la base de données BOLD et établir une base de données génétiques, incluant des marqueurs génétiques additionnels, en exploitant les spécimens de chéloniens saisis par le gouvernement. Une méthode rapide et précise pour authentifier les échantillons saisis permettra d'aider les agences gouvernementales à poursuivre les criminels et à limiter l'exploitation illégale de chéloniens sauvages. [Traduit par la Rédaction] Mots-clés: COI, tortue, tortue terrestre, tortue d'eau douce, BOLD., Introduction Chelonians (Order Testudines) have long been exploited by humans. The ancient Chinese began carving words on turtle plastrons for record-keeping and auguring at least 3000 years ago (Sung 2013), [...]

Background: While polyploids are common in plants, the evolutionary history and natural dynamics of most polyploid groups are still unclear. Owing to plentiful earlier systematic studies, Ludwigia sect. Isnardia (comprising 22 wetland taxa) is an ideal allopolyploid complex to investigate polyploid evolution and natural dynamics within and among taxa. With a considerable sampling, we concentrated on revisiting earlier phylogenies of Isnardia, reevaluating the earlier estimated age of the most recent common ancestor (TMRCA), exploring the correlation between infraspecific genetic diversity and ploidy levels, and inspecting interspecific gene flows among taxa. Results: Phylogenetic trees and network concurred with earlier phylogenies and hypothesized genomes by incorporating 192 atpB-rbcL and ITS sequences representing 91% of Isnardia taxa. Moreover, we detected three multi-origin taxa. Our findings on L. repens and L. sphaerocarpa were consistent with earlier studies; L. arcuata was reported as a multi-origin taxon here, and an additional evolutionary scenario of L. sphaerocarpa was uncovered, both for the first time. Furthermore, estimated Isnardia TMRCA ages based on our data (5.9 or 8.9 million years ago) are in accordance with earlier estimates, although younger than fossil dates (Middle Miocene). Surprisingly, infraspecific genetic variations of Isnardia taxa did not increase with ploidy levels as anticipated from many other polyploid groups. In addition, the exuberant, low, and asymmetrical gene flows among Isnardia taxa indicated that the reproductive barriers may be weakened owing to allopolyploidization, which has rarely been reported. Conclusions: The present research gives new perceptions of the reticulate evolution and dynamic nature of Isnardia and points to gaps in current knowledge about allopolyploid evolution. [ABSTRACT FROM AUTHOR]

Premise of the Study: Interpreting relationships within groups containing polyploids, which are frequent in angiosperms, can be greatly assisted by genomic techniques. In this study, we used a genome‐skimming approach to investigate the evolutionary relationships and origins of polyploids in the monophyletic group, Ludwigia section Macrocarpon (Onagraceae), which includes diploid, tetraploid, and hexaploid taxa. Methods: We sampled all known taxa and ploidy levels in the section and conducted shotgun sequencing. We assembled plastomes, mitochondrial sequences, and completed nuclear ribosomal regions, reconstructed phylogenies, and conducted comparative genomic analyses for plastomes to gain insights into the relationships among studied taxa. Key Results: Within the section, results showed that the South American diploid taxa L. bonariensis and L. lagunae were closely related. We reported the first chromosome count (2n = 4× = 32) for L. neograndiflora, which is closely related to the two South American diploid taxa, although its exact origin remains unclear. The samples of the widespread, polyploid taxon L. octovalvis do not form a monophyletic group. Both tetraploid and hexaploid L. octovalvis lineages have originated more than once. At least one tetraploid in the L. octovalvis lineage may have been involved in the origins of hexaploids. One or more extinct/unsampled intermediate tetraploids in the L. octovalvis lineages had also likely been involved in the origins of hexaploids. Conclusions: Genome skimming provided important insights into the complex evolutionary relationships within sect. Macrocarpon, but additional sampling and data from single‐copy nuclear regions are necessary to further elucidate the origins of the polyploids in this section. [ABSTRACT FROM AUTHOR]

Species identification based on the DNA sequence of a fragment of the cytochrome c oxidase subunit I gene in the mitochondrial genome, DNA barcoding, is widely applied to assist in sustainable exploitation of fish resources and the protection of fish biodiversity. The aim of this study was to establish a reliable barcoding reference database of the native ray-finned fishes in Taiwan. A total of 2993 individuals, belonging to 1245 species within 637 genera, 184 families and 29 orders of ray-finned fishes and representing approximately 40% of the recorded ray-finned fishes in Taiwan, were PCR amplified at the barcode region and bidirectionally sequenced. The mean length of the 2993 barcodes is 549 bp. Mean congeneric K2P distance (15.24%) is approximately 10-fold higher than the mean conspecific one (1.51%), but approximately 1.4-fold less than the mean genetic distance between families (20.80%). The Barcode Index Number ( BIN) discordance report shows that 2993 specimens represent 1275 BINs and, among them, 86 BINs are singletons, 570 BINs are taxonomically concordant, and the other 619 BINs are taxonomically discordant. Barcode gap analysis also revealed that more than 90% of the collected fishes in this study can be discriminated by DNA barcoding. Overall, the barcoding reference database established by this study reveals the need for taxonomic revisions and voucher specimen rechecks, in addition to assisting in the management of Taiwan's fish resources and diversity. [ABSTRACT FROM AUTHOR]

Background: Domestic cats are important companion animals in modern society that live closely with their owners. Mislabeling of pet food can not only harm pets but also cause issues in areas such as religious beliefs and natural resource management. Currently, the cat food market is booming. However, despite the risk that mislabeling poses to cats and humans, few studies have focused on species misrepresentation in cat food products., Methods: To address this issue, we used DNA barcoding, a highly effective identification methodology that can be applied to even highly processed products. We targeted a short segment (~85 basepairs) of the mitochondrial 16S rRNA ( 16S ) gene as a barcode and employed Sanger or next generation sequencing (NGS) to inspect 138 canned cat food products in the Taiwanese market., Results: We discovered that the majority of mislabeling incidents were related to replacement of tuna with other species. Moreover, our metabarcoding revealed that numerous undeclared ingredients were present in all examined canned products. One product contained CITES Appendix II-listed shortfin mako shark ( Isurus oxyrinchus ). Overall, we uncovered a mislabeling rate of at least 28.99%. To verify cases of mislabeling, an official standardized list of vernacular names, along with the corresponding scientific species names, as well as a dependable barcoding reference sequence database are necessary., Competing Interests: The authors declare that they have no competing interests., (© 2024 Wang et al.)