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Reliable delimitation and identification of species is central not only to systematics, but also to studies of biodiversity, ecology and pest management. In the era of Internet-based biodiversity databases misidentifications are rapidly disseminated and may have far-reaching consequences. Leafhoppers from the genus Aphrodes ( Hemiptera, Cicadellidae) are common and abundant, but, nevertheless, they are still a taxonomically challenging group whose members are often assessed in ecological studies and are also potential vectors of plant diseases. Previous study has shown that the syntype series for A. aestuarina ( Edwards) includes also specimens of A. makarovi Zachvatkin and has suggested that misidentifications may be widespread in museum collections. We studied Aphrodes individuals collected from the U.K. and Slovenia in order to provide a more comprehensive analysis of this genus using multiple criteria. Combined work using male and female vibrational signals emitted during courtship, and a 600-bp fragment within the barcoding region of the COI mtDNA gene, provided validated specimens that we also used for morphometric study. Analyses confirmed A. aestuarina, A. bicincta, A. diminuta and A. makarovi as behaviourally, genetically and morphologically distinct species. Although any of these approaches could be used alone to distinguish between species, combining morphological and molecular approaches will help to improve reliability, especially when identifying females. Morphological investigation of validated individuals from the U.K. and Slovenia also revealed geographic differences within species. By combining several body and aedeagus morphological characters males can be reliably identified, however, morphological differences between species are, nevertheless, relatively small. By contrast, observed genetic distances between Aphrodes species are relatively large (4.2-7.0%). At about half of our collecting sites more than one Aphrodes species was found and A. makarovi was collected together with every other species, including A. aestuarina on tidal saltmarshes. Due to low morphological variation between syntopic congeners it is likely that many museum specimens of Aphrodes have been assigned to the wrong species and species identification in ecological and vector studies may also be questionable. [ABSTRACT FROM AUTHOR]

The article offers information on the International Association for Statistical Education (IASE). As stated, IASE, which is a formally constituted education section of the International Statistical Institute (ISI), focuses on improving statistics education at all levels from elementary school through the training of professionals and to increase the uptake of statistics education across the world. The association has around 800 members, which largely comprise of teachers, lecturers and professors of statistics, researchers in the field of statistics education and applied and government statisticians with an interest in statistics education.

The purpose of the investigation was to determine the meanings attached by students to the different kinds of molecular structure representations used in chemistry teaching. The students (n = 124) were from primary (aged 13-14 years) and secondary (aged 17-18 years) schools and a university (aged 21-25 years). A computerised 'Chemical Visualisation Test' was developed and applied. The research indicates that students' appreciation of three-dimensional molecular structures differs according to the kind of representation used. The best results were achieved with the use of concrete, and pseudo-concrete types of representations (e.g. three-dimensional models, their photographs, computer-generated models). However, the use of more abstract types (e.g. schematic representations, stereochemical formula) was less effective. A correlation between students' results on the Chemical Visualisation Test and their educational level, spatial visualisation, and spatial relations skills was shown statistically, but no statistically significant gender differences were observed. [ABSTRACT FROM AUTHOR]