A comprehensive DNA barcode inventory of Austria's fish species

DNA barcoding and cryptic diversity in fishes from the Ili River Valley in China, Xinjiang

The Ili River Valley, located in the northwest of China, serves as a vital repository for fish genetic resources. Its extensive water network and diverse climate have given rise to a unique fish composition and endemic species. In this study, we collected the cytochrome c oxidase subunit I (COI) sequences from 660 fish specimens in the Ili River Valley. The effectiveness of DNA barcoding in identifying fish species in the area was assessed by examining genetic distances, constructing phylogenetic trees, and performing ABGD (Automatic Barcode Gap Discovery) analyses, among other methods. In total, 20 species were identified, including one unidentified species (Silurus sp.). Except for Silurus asotus and Hypophthalmichthys molitrix (only one sample), the maximum intraspecific genetic distance among the remaining species was smaller than the minimum interspecific distance, which proves that the species exhibit obvious barcode gaps. In the Neighbor-Joining trees, 20 species formed separate monophyletic branches. According to ABGD analysis, 660 sequences were categorized into 19 Operational Taxonomic Units, with Silurus sp. and S. asotus grouped into a single OTU. The Silurus in this study exhibits shared haplotypes and significant genetic divergence, suggesting the potential presence of cryptic species. Furthermore, the nucleotide diversity across all species fell below the threshold level, indicating that the local fish population is gradually declining. In conclusion, this study has demonstrated the effectiveness of DNA barcoding in identifying fish species in the Ili River Valley, providing valuable data to support the conservation of local fish resources.

The expansion of invasive species to the East: new sites of the bullheads (genus Ameiurus Rafinesque 1820) in Ukraine with morphological and genetic identification

This study confirms the extended distribution of two invasive species of the genus Ameiurus in Ukraine. Specifically, A. melas is recorded for the first time in the Southern Buh basin and A. nebulosus has expanded further eastward within the Dnipro basin. Material collected in 2019 and 2022 was identified by morphological features and confirmed by molecular genetic analysis. The most reliable morphological characters for distinguishing these two species include anal-fin membrane pigmentation (light or black), gill raker count (fewer or more than 16), and serrations on the pectoral-fin spine (well-developed along the full length or small, absent near the tip). The analysis of the cytochrome oxidase subunit I barcoding marker identified all samples from the Dnipro Basin (Tnia and Velykyi Luh localities) as A. nebulosus, while all specimens from the Vinnytsia region within the Southern Buh basin (Sotskoho and Vyshenske lakes) were attributed to A. melas. The maximum-likelihood analysis revealed clearly separated clades with high bootstrap support (>75%), strongly supporting the presence of the two separate species. This study suggests the potential for further eastward expansion of both species within Ukraine: A. nebulosus in the northern direction and A. melas in the southern direction.

An annotated catalogue of selected historical type specimens, including genetic data, housed in the Natural History Museum Vienna

Museum collections are an important source for resolving taxonomic issues and species delimitation. Type specimens as name-bearing specimens, traditionally used in morphology-based taxonomy, are, due to the progress in historical DNA methodology, increasingly used in molecular taxonomic studies. Museum collections are subject to constant deterioration and major disasters. The digitisation of collections offers a partial solution to these problems and makes museum collections more accessible to the wider scientific community. The Extended Specimen Approach (ESA) is a method of digitisation that goes beyond the physical specimen to include the historical information stored in the collection. The collections of the Natural History Museum Vienna represent one of the largest non-university research centres in Europe and, due to their size and numerous type specimens, are frequently used for taxonomic studies by visiting and resident scientists. Recently, a version of ESA was presented in the common catalogue of the Fish and Evertebrata Varia collections and extended to include genetic information on type specimens in a case study of a torpedo ray. Here the case study was extended to a heterogeneous selection of historical type series from different collections with the type locality of Vienna. The goal was to apply the ESA, including genetic data on a selected set of type material: three parasitic worms, three myriapods, two insects, twelve fishes, and one bird species. Five hundred digital items (photographs, X-rays, scans) were produced, and genetic analysis was successful in eleven of the 21 type series. In one case a complete mitochondrial genome was assembled, and in another case ten short fragments (100-230 bp) of the cytochrome oxidase I gene were amplified and sequenced. For five type series, genetic analysis confirmed their taxonomic status as previously recognised synonyms, and for one the analysis supported its status as a distinct species. For two species, genetic information was provided for the first time. This catalogue thus demonstrates the usefulness of ESA in providing digitised data of types that can be easily made available to scientists worldwide for further study.

Cobitis feroniae, a new spined loach from southern Latium, Italy (Teleostei: Cobitidae)

Cobitis feroniae, new species, is described from central Italy. It is distinguished from C. zanandreai, its putatively closest relative, by having several, small, black dots below Z4; minute, black spot at the upper caudal peduncle, and the pigmentation in Z2 separated from pigmentation in Z1 anterior to the dorsal-fin origin. It is further distinguished from C. zanandreai by having 13 diagnostic nucleotide substitutions in the mtDNA COI barcode region, and a K2P nearest-neighbour distance of 2.9%.

A DNA barcode library of Austrian geometridae (Lepidoptera) reveals high potential for DNA-based species identification

Situated in the Eastern section of the European Alps, Austria encompasses a great diversity of different habitat types, ranging from alpine to lowland Pannonian ecosystems, and a correspondingly high level of species diversity, some of which has been addressed in various DNA barcoding projects. Here, we report a DNA barcode library of all the 476 species of Geometridae (Lepidoptera) that have been recorded in Austria. As far as possible, species were sampled from different Austrian regions in order to capture intraspecific genetic variation. In total, 2500 DNA barcode sequences, representing 438 species, were generated in this study. For complete coverage of Austrian geometrid species in the subsequent analyses, the dataset was supplemented with DNA barcodes from specimens of non-Austrian origin. Species delimitations by ASAP, BIN and bPTP methods yielded 465, 510 and 948 molecular operational taxonomic units, respectively. Congruency of BIN and ASAP partitions with morphospecies assignments was reasonably high (85% of morphospecies in unique partitions), whereas bPTP appeared to overestimate the number of taxonomic units. The study furthermore identified taxonomically relevant cases of morphospecies splitting and sharing in the molecular partitions. We conclude that DNA barcoding and sequence analysis revealed a high potential for accurate DNA-based identification of the Austrian Geometridae species. Additionally, the study provides an updated checklist of the geometrid moths of Austria.

Parasites and their impact on thick-shelled river mussels Unio crassus from two populations in Luxembourg

The thick-shelled river mussel Unio crassus Philipsson, 1788 is a species native to many European habitats, with declining populations. The impact of parasite communities on health status of this species is poorly understood. In this study, parasites of 30 U. crassus specimens from the Our and Sauer Rivers in Luxembourg were identified morphologically and, in some cases, using molecular genetic methods. The findings were correlated to selected parameters (total length, visceral weight, shell lesions, gonadal stage). The 2 populations did not differ in shell length, visceral weight, number of males and females, gonadal scoring, shell lesions, and the occurrence of glochidia. The prevalence and infestation intensities of detected Trichodina sp., Conchophthirus sp., and freshwater mite larvae did not differ between the 2 populations, whereas the prevalence and infestation intensities of mite eggs, nymphs, and adults were significantly higher in the Sauer River. Rhipidocotyle campanula and European bitterling Rhodeus amarus larvae were only present in the Sauer. Histopathology revealed the destruction of the gonads by R. campanula and tissue damage by the mites. The only significant correlation of the selected parameters was a positive correlation between R. amarus occurrence and total length as well as a negative correlation between R. amarus occurrence and gonadal stage. In the Sauer River, 2 mussels were found to be hermaphrodites.