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…
At a ditch near Tribsees in northeastern Germany a young individual of the freshwater snail Lymnaea stagnalis was photographed while attached to the dorsum of the abdomen of a female Aeshna viridis, after the odonate took off after oviposition in Stratiotes aloides. This is the first known case for odonate-born dispersal of freshwater gastropods.
Behaviour of dragonflies was observed during the partial solar eclipse in Saitama, Japan, on 22 July 2009. The solar eclipse started at 09:54 h, reached its maximum magnitude of 74.9% at 11:12 h, and ended at 12:29 h. Light intensity at the peak of the eclipse was 1005 lx, a reduction by 28.2% of that…
A comparative study of female external genitalia was carried out in representatives of three dragonfly families that lay eggs exophytically, with special emphasis placed on skeletal musculature and sensilla. Female external genitalia are characteristically represented by the vulvar lamina and rudiments on the 9th sternum. In a gomphid, Gomphus vulgatissimus, and a corduliid, Cordulia aenea,…
From 12 to 25 August 2009, the odonate fauna of Santo Antão, Cape Verde was surveyed by recording adults and collecting larvae and exuviae at 26 localities, mostly situated in the northwest of the island. Based on the results of this survey and literature data on the Cape Verdes it appears that the resident odonate…
The East Palaearctic Coenagrion glaciale and C. hylas are characterized by a current disjunct distribution. New data from northern European Russia significantly modify the earlier known pattern of their distribution. The first European records of C. glaciale and a new record of C. hylas west of the Urals are reported from the environs of Pinega…
Elasmothemis rufa sp. nov. (holotype: Venezuela, Amazonas, Río Cataniapo), Macrotbemis taurepan sp. nov. (holotype: Venezuela, Bolívar, El Paují), and Oligoclada garrisoni sp. nov. (holotype: Venezuela: Amazonas, San Fernando de Atabapo) are described and illustrated. All holotypes are deposited at MIZA. Macrothemis heteronycha and Micrathyria paruensis are recorded from Venezuela for the first time, and Micrathyria…
Guardians of the watershed. Global status of dragonflies: critical species, threat and conservation Viola Clausnitzer, Reinhard jodicke International Journal of Odonatology, Volume 7, Issue 2, Page i, 2004https://doi.org/10.1080/13887890.2004.9748201Published: 1 July 2004 Full text PDF Copyright information Issue section: Introduction
Larval growth rate has the same temperature coefficient in three species of coenagrionids, but Argia vivida and Amphiagrion abbreviatum, which frequently live in geothermally heated water, grow fastest at 29.0–30.0°C compared with 23.4°C for Coenagrion resolutum, which lives in cooler water. Survival below 15°C in the laboratory was much better in C. resolutum. These characteristics…
The mycoflora developing on dead specimens of 11 species of dragonfly, collected while floating on the water surface, was investigated under laboratory conditions. Sixty-six zoosporic fungus species were found to grow on the fragments of dragonfly investigated, including 15 Chytridiomycetes and 51 Oomycetes. Of these 66 species, 18 are known as parasites or necrotrophs of