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A new species of the genus Obtusicauda Soliman, 1927 (Hemiptera: Aphididae: Aphidinae: Macrosiphini) is described and illustrated from North-Khorasan province, Iran: Obtusicauda iranicasp. n. The species is described based on apterous viviparous females, an alate viviparous female and oviparous females found living on the terminal parts of shoots of Artemisia sieberi, A. kopetdaghensis, A. scoparia and Artemisia sp. (Asteraceae). The new species is morphologically most similar to Obtusicauda dolychosiphon (Umarov, 1964). This holocyclic aphid is not typically attended by ants. [ABSTRACT FROM AUTHOR]

Greenbug, Schizaphis graminum (Rondani) (Hemiptera: Aphididae), is one of the most destructive pests of wheat. Potential resistance of wild wheat, Triticum boeoticum, was quantified as the number of aphids, aphid load (number of aphids/plant dry biomass), percentage of alate (winged) individuals produced, and winged S. graminum aphids settled. Fewest aphids were on TbKu11 and TbKu1. The lowest aphid load was on TbKu7 and TbKu1. The largest percentages of winged aphids were on TbL9, TbAE2 and TbKu6. Preference tests were designed for eight populations selected based on results of performance tests. The largest number of winged aphids settled on each plant was on Pishtaz and the least was on TbKu1. The largest and smallest numbers of first-instar nymphs were produced by winged individuals on Pishtaz and TbKu1, respectively. Based on results, TbKu1 has relative resistance against S. graminum and could be a candidate for investigation of genomes to detect mechanisms of molecular resistance to S. graminum. [ABSTRACT FROM AUTHOR]

The article discusses a study that examined the aphid species Liosomaphis atra Hille Ris Lambers living on Berberis (Berberidaceae), a large genus of deciduous and evergreen shrubs in Iran.

Morphometric analyses were carried out on some populations of Aphis craccivora Koch (Hemiptera: Aphididae) associated with different host plants. Twelve morphological characters were measured. Two multivariate discriminant analyses, Canonical variates analysis and Cluster analysis were employed to discriminate individuals of A. craccivora populations on a morphological basis. Both Canonical variates analysis and Cluster analysis revealed significant differences among A. craccivora collected from different host plants. A stepwise Canonical variates analysis selected four morphological characters (siphunculus length, ultimate rostral segment length, basal diameter of siphunculus and processus terminalis length) from which two (siphunculus length and ultimate rostral segment length) showed the highest contribution to the separation of host-associated populations and 87.6% of individuals were reclassified correctly into their original populations. The result of morphometric analyses performed here revealed the existence of three morphologically differentiated groups within A. craccivora associated with different host plants which provide evidence for the presence of host related forms. This study demonstrates that morphometric analysis of morphological characters can discriminate among host related groups based on size variation and clearly separates the individuals of A. craccivora. The aphid population associated with Robinia pseudoacacia L. was clearly separated from other populations. The most important discriminatory characters of A. craccivora and their functions in relation to adaptation of populations with different host plant species are discussed. We concluded that A. craccivora populations are not homogeneous morphological entities and represent different host-associated forms. The results presented here for the morphological structure of A. craccivora provide the framework to investigate the genetic and biological differences among these entities so that we could be able to exactly evaluate their taxonomic situation. [ABSTRACT FROM AUTHOR]

Multivariate morphometric studies are often carried out on different aphid taxa in order to analyze population variation and species discrimination in relation with different factors such as host plant, temperature and geography, which have significant effect on aphid morphology. The chrysanthemum aphid, Macrosiphoniella sanborni (Hemiptera: Aphididae), is a widespread pest on cultivated chrysanthemum throughout the world. In the present study 21 morphological characters in 11 populations of M. sanborni collected from several geographic locations in Iran were examined. Multivariate morphometric techniques, canonical variates analysis (CVA) and cluster analysis were used to determine whether these populations can be reliably morphologically discriminated. The results showed such discrimination between populations. The Kermanshah population (located in western Iran) clearly separated from other populations, indicating the presence of a morphologically distinct group. It could be concluded that presence of a geographic barrier and climatic conditions are among the most important factors which contribute to the differentiation between populations. Other complimentary studies such as genetic investigation will provide a better understanding of the evolutionary implications of the population structure. [ABSTRACT FROM AUTHOR]