Redescription of the holotype of Mecistogaster pronoti Sjöstedt, 1918 (Zygoptera: Pseudostigmatidae)

Mecistogaster pronoti Sjöstedt, 1918 was described based on a female holotype deposited in the Naturhistoriska Riksmuseet, Stockholm, collected in the state of Espírito Santo, Brazil. The original description has no illustrations, which makes its identification very difficult. Herewith we redescribe and illustrate this holotype. The species is red listed and considerations regarding its conservation are…

Redescription of Erythrodiplax pallida (Needham, 1904) (Odonata: Libellulidae)

A redescription of both sexes of Erythrodiplax pallida (Odonata: Libellulidae) is provided based on specimens collected in shallow wetlands associated with flood plains from small streams to large rivers in Corrientes and Buenos Aires provinces, Argentina. The vesica spermalis morphology resembles those of the basalis and nigricans groups due to the presence of median and…

Preliminary list of Odonata from the Colombian Amazon, with descriptions of Inpabasis nigridorsum sp. nov. & Diaphlebia richteri sp. nov. (Coenagrionidae & Gomphidae)

The Colombian Amazon is one of the most biodiverse and unexplored regions in the world. Inventories and deeper research are needed for most of its biota, including for dragonflies. This work reports the results of a trip to the Amazon region in order to collect Odonata. It includes revision of CBUCES, CEUA and ICN entomological…

Local extinctions and range contraction of the endangered Coenagrion mercuriale in North Africa

Freshwater biodiversity is currently threatened worldwide. In North Africa, 24.4% of Odonata are regionally threatened with extinction. In this region, freshwater resources are particularly scarce and an increasing shortage of water is expected. To better understand the current threats to the endangered North African damselfly Coenagrion mercuriale we updated information on extinct and extant populations…

Behaviour and body size: plasticity and genotypic diversity in larval Ischnura elegans as a response to predators (Odonata: Coenagrionidae)

Phenotypic plasticity represents an adaptive tool in organisms including odonates to cope with heterogeneous environmental conditions. However, while some odonate species can occupy various changing habitats, other species are adapted to a narrow range of environmental conditions. Commonly, behavioural modifications are applied to avoid detection and encounters with predators. But reduced behavioural activity results in…

Differential survival rates of damselfly larvae in the presence of newt and dragonfly predators

The damselfly species Paracercion melanotum has been found to be the most abundant species in damselfly larval communities on Okinawa-zima Island in southwest Japan. To clarify differential susceptibility to predation, a possible factor affecting relative population densities in larval communities, between Paracercion melanotum and a less common damselfly species, Ischnura senegalensis, laboratory experiments were conducted…

Do coloured-winged damselflies and dragonflies have flight kinematics different from those with clear wings?

The flights of male odonates encountering conspecifics at their reproduction sites were investigated by means of slow-motion films. We recorded large and generally consistent differences between species with clear wings (SCLW) and species with coloured wings (SCOW). SCLW mostly fought having physical contact and moved their wings without pauses in wing beats (hereafter designated wing…

Rediscovery of Mesagrion leucorrhinum (Zygoptera: Megapodagrionidae): a “formal” description of female and ultimate stadium of larva with notes on habits

Adult female and ultimate stadium larva of Mesagrion leucorrhinum are formally described and illustrated based on material from three locations in Antioquia, Meta and Cundinamarca Departments, Colombia. The species is sexually dimorphic. The ♀ is distinguishable from other related genera by a pair of notches in the prothoracic anterior lobe and shares with Heteropodagrion and…