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…

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,…

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…

Habitat segregation of sympatric Mnais damselflies (Odonata: Calopterygidae): microhabitat insolation preferences and competition for territorial space

Distribution and abundance of sympatric Mnais costalis and M. pruinosa damselflies were studied in a low mountain stream in Shiga, Japan, from 2008 through 2012. The reproductive seasons of the two species overlapped almost entirely: both species emerged in early May and disappeared in late June each year. Males of both species hold territories within…

Larval habitat and behaviour of Phenes raptor (Odonata: Petaluridae): a review of current knowledge, with new observations

Phenes raptor is one of only two petalurid dragonflies with a documented non-fossorial larval lifestyle. There have been few reported observations of larvae and their habitat, and the behaviour and ecology of this unique South American species remain largely unknown. This paper provides a review of previously published and unpublished information, and new observations on…

Variation in fluctuating asymmetry among nine damselfly species

Fluctuating asymmetry (FA), measured as random deviations from bilateral symmetry, likely results from developmental disturbances by internal or environmental stresses. However, comparisons of FA in single damselfly species (Odonata: suborder Zygoptera) from stressed environments have often been inconclusive. We measured levels of FA among multiple species of damselflies from the same environment to determine the…

Two new species of Pyrrhargiolestes, with a key to the males (Odonata: Argiolestidae)

Two new species belonging to the endemic New Guinea genus Pyrrhargiolestes are described from Papua New Guinea: P. lamington sp. nov. (holotype: Mount Lamington, Oro Province, dep. in RMNH) and P. yela sp. nov. (holotype: Rossel Island, Milne Bay Province, dep. in USNM). The presumed male of P. aulicus is described for the first time….