Shifts in dragonfly community structure across aquatic ecotones

Dragonflies (Odonata: Anisoptera) are often used as indicators of habitat type and quality due to their varied use of aquatic and terrestrial habitats. Species differ in their preferences for lotic and lentic waters, but community changes across ecotones, or transitional zones between distinct habitats (e.g. lotic and lentic), are not well understood. We quantified dragonfly…

Assessment of the water quality and Odonata assemblages in three waterbodies in Ilara-Mokin, south-western Nigeria

This study investigated the biological water quality and Odonata assemblages in three waterbodies in Ilara-Mokin, with the aim of determining the ecological integrity of the ecosystems. Sampling of Odonata specimens was carried out over April–August, 2017 between 9.00am and 4.00pm under favourable conditions. Some physico-chemical parameters of the water such as dissolved oxygen, electrical conductivity,…

Dragonflies and damselflies (Odonata) from the wetland of the Rio Pandeiros, northern region of Minas Gerais State, Brazil, with a description of the male of Archaeogomphus vanbrinki Machado (Anisoptera: Gomphidae)

The Odonata from the Refúgio Estadual da Vida Silvestre do Rio Pandeiros (RVSP), located in the Cerrado domain, Minas Gerais State, Brazil, were rapidly surveyed. Sampling efforts were undertaken along the Rio Pandeiros margins during four sampling periods between the rainy (spring–summer) and dry seasons (autumn–winter) from July 2014 to April 2015. We sampled 97…

Dragonflies (Insecta: Odonata) as indicators of habitat quality in Mediterranean streams and rivers in the province of Barcelona (Catalonia, Iberian Peninsula)

In a field study carried out in 2011 and 2014 adult dragonflies were identified as a rapid and easy-to-use means of assessing habitat quality and biological integrity of Mediterranean streams and rivers in the province of Barcelona (Region Catalonia, Iberian Peninsula). The study included sampling sites from five different river catchments: Besòs, Foix, Llobregat, Ter…

A hotspot for threatened Mediterranean odonates in the Seybouse River (Northeast Algeria): are IUCN population sizes drastically underestimated?

Several odonate species are threatened in the Mediterranean basin and some of them show alarming decreasing trends. The distribution and population estimations provided by the IUCN are based on occasional field sampling or non-rigorous methodologies and could be erroneous and misleading. To obtain reliable estimations of the population size and distribution of three threatened species,…

The effects of odonate species abundance and diversity on parasitism by water mites (Arrenurus spp.): testing the dilution effect

Water mites (Arrenurus spp.) parasitize adult dragonflies. We collected dragonflies weekly at 11 waterbodies in Greenville Co. and Pickens Co., SC, USA, to: (1) compare parasitism prevalence across species, sites, and sampling periods; (2) test the hypothesis that prevalence correlates with host abundance; (3) test the hypothesis that prevalence is inversely related to host diversity…

Parthenogenetic Ischnura hastata revisited: present status and notes on population ecology and behaviour (Odonata: Coenagrionidae)

Populations of Ischnura hastata found in the Azores archipelago represent the only known example of parthenogenesis in the order Odonata. In this paper, we present results from fieldwork done on the islands of São Miguel, Pico, Santa Maria, and Graciosa, aimed at characterizing population ecology and habitat preferences of this species. Sampling of several ponds…