Alternative oviposition tactics in Zygonyx torridus (Kirby) (Odonata: Libellulidae): modes and sequential flexibility

Zygonyx torridus inhabits waterfalls, rapids and riffle sections. Males patrol over these sites. After copulation the partners perform an extensive search while flying in tandem over a wide range. Behavioural studies in Mauritius 1997 and 2014 showed that there is considerable plasticity in oviposition behaviour. Three main modes could be distinguished: (A) egg-laying in tandem…

Melanic individuals in color polymorphic Enallagma damselflies result from phenotypic, not genetic, variation

Genetically determined color polymorphisms have a long history in the study of evolutionary change acting on populations. The Odonata exhibit relatively high levels of sex-specific color polymorphisms in mature adults. In Ischnura and Coenagrion, female-specific polymorphisms are known to be controlled by Mendelian genes. Nearly half of Enallagma species have polymorphic females, but the inheritance…

Descriptions of two new Cephalaeschna species from Yunnan, China (Odonata: Aeshnidae)

Two new species, Cephalaeschna cornifrons sp. nov. and C. ordopapiliones sp. nov. from Yunnan Province, China, are described, illustrated in color and compared with known Chinese Cephalaeschna. All the holotypes are deposited in the Collection of Aquatic Animals, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan City, Hubei Province, China. Brief notes on biology of…

An emergence study of Petalura gigantea (Odonata: Petaluridae)

Emergence studies in Odonata provide information on the behaviour, ecology and fundamental demographic parameters in population studies. This paper reports on a study of sex ratio at emergence, pattern and duration of the emergence season, and potential cohort splitting in Petalura gigantea. Sex ratio at emergence varied among years, habitat patches and swamp types. Across

Three new Cephalaeschna species from central China with descriptions of the hitherto unknown sex of related species (Odonata: Aeshnidae)

Three new Cephalaeschna species, C. discolor sp. nov. (holotype male; Shennongjia National Nature Reserve, Shennongjia City, Hubei province, China, 16 August 2012), C. mattii sp. nov. (holotype male; Lujiahe River, Zigui County, Hubei province, China, 18 September 2012) and C. solitaria sp. nov. (holotype male; Dalongtan in Shennongjia National Nature Reserve, Shennongjia City, Hubei province,…

Morphometric and molecular studies on the populations of the damselflies Chalcolestes viridis and C. parvidens (Odonata, Lestidae)

Morphometric and genetic differences were analysed for two closely related damselflies, Chalcolestes viridis and C. parvidens. A total of 305 male individuals were collected from six European countries (Austria, Croatia, Germany, Greece, Hungary and Portugal). Measurements from a total of 28 populations of C. viridis and C. parvidens and several intermediate forms were collected to…

The larva of Nesolestes sp. from Madagascar (Odonata: Megapodagrionidae)

The larva of the genus Nesolestes is described and figured for the first time. Specimens were found in small brooklets in littoral swamp forest in south-eastern Madagascar. The larva is compared with the two other Madagascan genera of Megapodagrionidae, Protolestes and Tatocnemis, and diagnostic characters are given. The caudal lamellae are held in a horizontal…