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Morphometric and genetic differences were analysed for two closely related damselflies, Chalcolestes viridisand 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. viridisand C. parvidensand several intermediate forms were collected to determine if they can be definitely distinguished using simple morphometric characters. DNA sequences from two independent loci (nuclear ribosomal ITS region and mitochondrial cytochrome oxidase I gene) were analysed to test whether these taxa represent separate monophyletic groups as well as to compare the genetic distance with those found between well-accepted European Lestesspecies. Discriminant analysis revealed that C. viridisand C. parvidensare differentiated in morphometric space. Individuals with intermediate anal appendage traits overlapped with both C. viridisand C. parvidenswhich raised the possibility that they are merely subspecies of a single species. However, genetic analysis of both investigated DNA regions showed that the two Chalcolestestaxa did not share haplotypes, indicating their status as true species. Furthermore, they formed a monophyletic group separated from the investigated Lestesspecies, supporting the recognition of the genus Chalcolestes. The two Chalcolestesspecies are very closely related compared with European Lestesspecies, suggesting that their divergence occurred relatively recently.

A population of Amphora micrometraGiffen, collected in September 2002 from different habitats in Laguna Blanca in the Bolivian Altiplano, South America, has been examined using light transmission and scanning electron microscopy. The original description of this species is incomplete and insufficient to characterize the taxon in the light of the newly collected ultrastructural data. The holotype of A. micrometrawas examined during the present study and compared to Bolivian specimens. An emended diagnosis of A. micrometrausing all available information is provided. A taxonomic discussion based on available literature and the ecology of the taxon is also presented herein.

In a set of recent papers we have shown that the diffusion asymmetry in diffusion couples (the diffusion coefficient is orders of magnitude larger in one of the parent materials) leads to interesting phenomena: i) sharp interface remains sharp and shifts with non Fickian (anomalous) kinetics [1-5], ii) originally diffuse interface sharpens even in ideal (completely miscible) systems [6,7], iii) an initially existing thin AB phase in A/AB/B diffusion couple can be dissolved [8], iv) there exists a crossover thickness (typically between few nanometers and 1m) above which the interface shift turns back to the Fickian behaviour [9], v) the growth rate of a product of solid state reaction can be linear even if there is no any extra potential barrier present (which is the classical interpretation of the “interface reaction control” for linear kinetics) [10]. These latter results will be summarized and reformulated according to the usual expression for linear-parabolic law containing the interdiffusion coefficient, D, and interface transfer coefficient, K. Relation between the activation energies of D and K will be analyzed and compared with available experimental data.