Congruence of the composition of Odonata between dry and rainy seasons in the Maranhense Cerrado

In tropical streams, seasonality has a strong influence on heterogeneity, altering available resources and affecting the carrying of organisms, substrate and organic matter. This causes changes in the limnological variables, as well as in the species composition. The aim of our study was to evaluate the response of the congruence of the Odonata community in two seasons in streams of the transition between Cerrado and Caatinga.

The Odonata of Argentina: state of knowledge and updated checklist

An updated checklist of the 282 species of Odonata known to occur in Argentina is presented along with distributional information by province and ecoregion. Ten new records for the country and 87 new provincial records are provided. At present, 17 species of Odonata are considered endemic to Argentina, and distribution maps for each of them…

Emergence timing and fixation height in Pachydiplax longipennis (Odonata: Libellulidae) at varying substrate density and sunlight exposure

Emergence substrate and sunlight penetration inherently trade off in patchy vegetation. Given the importance of solar radiation at emergence, we expected greater sunlight availability in sparse vegetation to advance emergence timing and reduce the average height of emergence fixation. We used outdoor mesocosms stocked with varying cattail (Typha) densities and late-stage Pachydiplax longipennis (Odonata: Libellulidae)…

A scientometric study of the order Odonata with special attention to Brazil

The insects of the order Odonata have an aquatic larval stage and land-dwelling adults. These insects play an important role in aquatic ecosystems and are excellent bioindicators. The present study was based on a scientometric analysis of the research available on the Odonata, which aimed to identify the principal trends and gaps in the database…

First record of extra-abdominal processes in adult Odonata

Paired extra-abdominal processes (ap) were found in the pleural region of abdominal segments 6–9 in adult Odonata for the first time. They are unsegmented bulge-like or rod-like structures of different size, degree of sclerotization and movability. A short search across odonatan families has shown that ap are inherent for all studied Aeshnidae and for some…

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,…

Aspects of life history of Platycnemis subdilatata (Zygoptera: Platycnemididae) in Northeast Algeria

The determination of seasonal regulation is important to understand how species have adapted to their local environmental conditions. In this study, we investigate the life history of a North African endemic damselfly, Platycnemis subdilatata, in a northeast Algerian population. We combined field and laboratory investigations to assess the embryonic development, larval growth, emergence pattern and…