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

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.

Aquatic oligochaetes (Annelida: Clitellata) in reservoirs in São Paulo State: list of occurrence and ecological observations on the species

This work sought the survey of species and information about the distribution of the Class Oligochaeta in reservoirs sampled in the Sediment Quality Monitoring Network of CETESB (Environmental Company of the State of São Paulo). As such, this study aimed to inventory the limnic oligochaetes fauna to expand knowledge of the ecology and distribution of this group in reservoirs in the state of São Paulo. Ninety replicates were performed in 12 reservoirs in the state of São Paulo between 2014 and 2016, using van Veen or Ponar samplers in the sublittoral region, and Ekman-Birge in the deep region. Twenty-eight taxa were inventoried, belonging to the families Naididae and Opistocystidae. The species Dero righii and Pristina longisoma were recorded for the first time in São Paulo State, Nais magnaseta and Spirosperma velutina were first recorded in Brazil. The results presented here make this inventory extremely important for understanding the distribution of aquatic oligochaetes throughout the Brazilian territory.

A STUDY OF AQUATIC OLIGOCHAETES COMMUNITY IN THE UPPER PART OF AL- ABBASYIA RIVER / MIDDIE OF IRAQ

In the current study aquatic oligochaetes worms were collected monthly from five sites along AL- Abbasyia river / Al-Najaf province, South Iraq for a period between February 2018 to January 2019. Physical and chemical parameters for river water were examined which include: Air and Water temperature, pH ,Electrical conductivity ,Salinity, Dissolved oxygen , Biological oxygen demand and Sediment texture. The results showed a number of 5039 individuals of aquatic Oligochaeta were identified as three families Naididae ,Lumbriculdae and Enchytraaeidae .Tow species of Naididae Allonais pectinata (Stephenson, 1910) and Dero (Dero) dorsalis Forroniere, 1899 are considered as a new records in Euphrates River . Results showed the site S4 was highest number of worms site, 1323 worms of 17 species were found, while the lowest number of 579 individuals of 11 species were recorded in S2. J-card index for similarity showed that the highest similarity was between site S2 and site S3. Temporally, the highest individual numbers were recorded during September, while in April the lowest individual's number was recorded.

New species of aquatic oligochaetes (Annelida: Clitellata) from tufa barriers in Croatia

Two new aquatic oligochaete species are described from tufa barriers in Croatia. The reproductive system in the phallodriline Aberrantidrius mihaljevici Vučković et al. n. sp. conforms to the general pattern in the genus but it is distinguished by a combination of characters, including the shape and length of penial chaetae (3 times the mean length of somatic chaetae), atrium shape and spermathecal pore position (anterior in the postatrial segment). The lumbriculid Stylodrilus tofaceus Rodriguez et al. n. sp. is mainly distinguished from congeners by the spindle-shaped spermathecal ducts with high lining epithelium, and position of the spermathecal pores. These two new taxa reveal that aquatic oligochaete communities in tufa barriers of karstic regions may be of particular interest with respect to diversity of endemic taxa, and also for study of colonization routes of this interesting habitat, with possible relations with groundwaters. The finding of one specimen attributable to the genus Eclipidrilus may open ainteresting research on the biogeography of this Nearctic genus.

The aquatic oligochaete fauna of Lake Çıldır, Ardahan-Kars, Turkey, including an updated checklist of freshwater annelids known to occur in the country

In this paper, we present the results of the first survey for aquatic oligochaetes in Lake Çıldır, northeastern Turkey, during which 22 oligochaete species were recorded from the lake. The results of this survey were integrated into an updated and annotated list of oligochaetes and other aquatic annelids occurring in the country, summarized from historical and recent publications. Currently, the freshwater annelid fauna of Turkey includes 150 species of oligochaetes (1 Crassiclitellata, 21 Enchytraeidae, 1 Propappidae, 1 Haplotaxidae, 4 Lumbriculidae, 56 Naidinae, 64 Tubificinae, 2 Lumbricidae), 1 species of Branchiobdellida, and 6 species of Aphanoneura (1 Potamodrilidae and 5 Aeolosomatidae). Although studies focusing on the aquatic oligochaete fauna of Turkey have increased over the past 15–20 years, species diversity still remains unclear.

Citations for the published proceedings of our 14 International Symposia on Aquatic Oligochaetes (1979–2018)

These special publications, below, present overviews of and papers presented during our triennial international symposia on aquatic oligochaete biology. Three similar names for our symposia have been used since we began as a group in 1979: International Symposium on Aquatic Oligochaete Biology (ISAOB), International Symposium on Aquatic Oligochaetes (ISAO), and International Symposium on Aquatic Oligochaeta (ISAO).

On spermatophore-producing aquatic microdrile oligochaetes (Annelida: Clitellata)

The formation of encapsulated spermatophores is exceptional among aquatic oligochaetes, although it seems to have occurred independently in several unrelated taxa. Among the microdriles, some variations appear unique to single species. The recently described lumbriculid Uktena riparia Fend et al. forms spermatophores in the male duct and attaches them within a deep spermathecal bursa. The attachment of spermatophores to the body wall, in the clitellar region, or in the vicinity of male or spermathecal pores has been reported in Paranadrilus Gavrilov, Bothrioneurum Štolc and some Aktedrilus Knöllner species. Anatomical comparison of reproductive organs suggests convergent development of glandular organs in the male duct or spermathecae, used for the formation, transfer and/or attachment of spermatophores to the concopulant worms. The presence of similar organs in Smithsonidrilus Brinkhurst, where spermatophores have not been reported, is also discussed. Furthermore, a lectotype is designated for Paranadrilus descolei Gavrilov, 1955.