Ecological correlates of odonate assemblages of a Mediterranean stream, Wadi Cherf, northeastern Algeria: implications for conservation

We investigated the odonates of Wadi Cherf, a tributary of Wadi Seybouse, and explored the main environmental factors that may be important drivers of the abundance and diversity of Odonata assemblages. PCA analyses demonstrated a significant altitudinal gradient associated with water flow, temperature, vegetation cover, substrate and adjacent land use. Notably, pollution was a dominant…

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…

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…

The life history of a temperate zone dragonfly living at the edge of its range with comments on the colonization of high latitudes by Neotropical genera of Zygoptera (Odonata)

Of the many Zygopteran genera that occur in the Neotropics, only five (Hetaerina, Archilestes, Lestes, Argia, and Ischnura) are represented north of 40°N in North America, and only three of these (Hetaerina, Archilestes, and Argia) probably had a tropical origin. In the two genera of Lestidae (Archilestes and Lestes) the life history of temperate-zone populations…