Aquatic Oligochaeta (Annelida: Clitellata) in wetlands and irrigated rice fields in the state of Rio Grande do Sul (Southern Brazil)

ABSTRACT The knowledge of the diversity and distribution of aquatic Oligochaeta (Annelida: Clitellata) species is scarce in southern Brazil. This study presents a list of the species of aquatic Oligochaeta in wetlands and irrigated rice fields in the state of Rio Grande do Sul. Collections were carried out in two large wetland remnants and seven irrigated rice fields distributed in three regions across the state. We recorded eight species from two families (Alluroididae and Naididae). We expanded the distribution ranges of two species (Brinkhurstia americana and Stylaria lacustris), which represent new records for the state of Rio Grande do Sul and registered their occurrence in non-documented environments. In specific, the present study increases to 24 species the aquatic Oligochaeta diversity for the state of Rio Grande do Sul. In addition, the spatial distribution of the species recorded suggests that rice fields support a subset of the wetland fauna of aquatic Oligochaeta. The results provide important information on the ecology and distribution of limnic Oligochaeta and are useful to inform on the diversity of this fauna in agroecosystems.

Proceedings of the 14th International Symposium on Aquatic Oligochaeta (Table of Contents)

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Proceedings of the 14th International Symposium on Aquatic Oligochaeta (Cover)

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PREFACE: 14th International Symposium on Aquatic Oligochaeta

This volume is the proceedings for the 14th International Symposium on Aquatic Oligochaeta (ISAO), held in Hirosaki, Aomori Prefecture, Honshu, Japan, from 9 through 14 September 2018, organized by the Department of Natural Science, Faculty of Education, Hirosaki University, Hirosaki. The symposium was attended by 43 participants from 16 countries who presented 30 oral and 6 poster contributions. The scientific sessions were convened at the Iwaki Conference Hall in the 50th Anniversary Auditorium, Hirosaki University. In addition to the scientific sessions, there was a one-day excursion to visit a traditional playhouse Kouraku-Kan, lunch along the edge of Lake Towada – an oligotrophic caldera lake, and hiking along the lake’s outlet stream, Oirase-Keiryu, flowing through a cool temperate forest typical of northern Honshu. The symposium organizing committee consisted of Akifumi Ohtaka, Kimio Hirabayashi, Katsutoshi Ito, Mana Ito, Takaaki Torii, Naoya Kimura, Stuart R. Gelder, and Mark J. Wetzel, with invaluable support from students from Hirosaki University.

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).

Distributional patterns of aquatic Oligochaeta communities (Annelida: Clitellata) in running waters in Serbia

The study of aquatic Oligochaeta in freshwaters in Serbia contributes to the oligochaete fauna inventory of the Balkans. Based on our results and literature review, 97 species (45 genera from 8 families) are listed in the running waters of Serbia. From the list of 61 species recorded during our investigation, 12 were noted for the first time. The ecological analysis of Oligochaeta communities showed the largest participation of potamal and rhithral species. As regards current preferences, rheolimnophilous species predominated, and with respect to feeding type, collectors prevailed. Most of the species are tolerant to moderate and high organic load. According to microhabitat preferences, three types of rivers stood out, as follows: (1) pelophilous (dominance of L. hoffmeisteri); (2) psammophilous (dominance of S. heringianus); (3) phytophilous (dominance of N. bretscheri). Analyses of the relation to different types of waterbodies showed regularity in the distribution of oligochaetes, with a higher species richness in main watercourses (types 1 and 2), and a lower species richness in tributaries (types 3, 4 and 6). According to the dominant taxa, the running waters of Serbia can be classified into four groups which are characterized by the prevalence of naidids (naidins and tubificins), enchytraeids and lumbriculids. Our results show that community composition is a good indicator of the horizontal distribution of Oligochaeta.