DNA barcoding of Naididae (Annelida, Oligochaeta), based on cytochrome C oxidase gene and ITS2 region in China

Abstract

Exploring the effectiveness of DNA barcoding in species identification is a prerequisite for biodiversity conservation and environmental monitoring. Aquatic oligochaetes could serve as excellent indicators in aquatic monitoring programmes. However, few studies have examined the effectiveness of DNA barcoding in these specific organisms. The mitochondrial cytochrome C oxidase (COI) gene of 83 specimens belonging to 40 species of 18 genera were sequenced in this study. The results showed that there was a barcode gap between species of Naididae and the intraspecific genetic distances of each species were smaller than interspecific genetic distances. The classification results of ABGD (Automatic Barcode Gap Discovery) were consistent with those of morphological identification, except for Tubifex tubifex and Lumbriculus variegatus. All species were successfully distinguished in the phylogenetic tree, based on the ITS2 region, which was coincident with the morphological result. Our results provided evidence that DNA barcoding can be used as an effective and convenient tool for species identification of the family Naididae and even for other aquatic oligochaetes.

An Annotated Checklist of the Main Representatives of Meiobenthos from Inland Water Bodies of Central and Southern Vietnam—II—Annelid Worms (Oligochaeta and Aeolosomatidae)

“…At the same time, the presence of a significant number of species previously unknown in Vietnam in the material studied by us and collected only in a few provinces, along with several new and possibly new ones, suggests, in our opinion, a much greater diversity of aquatic annelids, both directly in the country and in the surrounding territories. In addition, one should also consider the still poorly studied groups in the region such as Tubificinae, Enchytraeidae and Aeolosomati-dae [5,21,23,27], as well as the possible presence of complexes of cryptic species among some of the worms we noted, traditionally (without using molecular methods) defined as a single species [46,47,59,97]. Thus, the prospects for further studies of the composition and diversity of aquatic annelids in Vietnam are obvious.…”

“…Remarks: According to recent molecular studies, A. pluriseta probably represents a complex of morphologically similar species [97]. 55 Population structure and abundance: In the majority of the listed samples, 1-5 individuals were assigned to this group of species, less often up to 8-9 individuals (in {6, 28, 29, 34}), and a maximum of 21-29 individuals (in {62, 90}).…”

Genetic variation of chigger mites in the Republic of Korea

“…Although the ITS2 of the three Leptotrombidium species in ROK was homogenized, the genotypes of the species in the COI was quite divergent in this study. The COI region may not be enough to evaluate the species boundary in certain taxon due to the fast evolution rate with genetic variation (Achurra & Erséus 2013;Roy et al 2010;Zhou et al 2021).…”