The wheat curl mite (WCM), Aceria tosichella Keifer, is a major pest of cereals worldwide. It is also a complex of well-defined genetic lineages with divergent physiological traits, which has not been accounted for in applied contexts. The aims of the study were to model the thermal niches of the two most pestiferous WCM lineages, designated MT-1 and MT-8, and to assess the extent to which temperature determines the distribution of these lineages. WCM population dynamics were modeled based on thermal niche data from March to November on the area of Poland (>311,000 km2). The most suitable regions for population development were predicted and compared to empirical field abundance data. Congruence between modeled parameters and field data for mite presence were observed for both WCM lineages although congruence between modeled thermal suitability and mite field abundance was observed only for MT-8. Thermal niche data for MT-1 and MT-8 provide biological insights and aid monitoring and management of WCM and the plant viruses it vectors. The presented models accurately estimate distributions of WCM and can be incorporated into management strategies for both current and predicted climate scenarios.

Passively dispersing organisms should optimise the time and direction of dispersal by employing behaviours that increase their probability of being successfully transported by dispersal agents. We rigorously tested whether two agriculturally important passively-dispersing eriophyoid species, wheat curl mite (WCM) and cereal rust mite (CRM), display behaviours indicating their readiness to depart from current host plants in the presence of potential dispersal cues: wind, an insect vector and presence of a fresh plant. Contrary to our expectations, we found that both species decreased their general activity in the presence of wind. When exposed to wind, WCM (but not CRM) significantly increased behaviour that has previously been considered to facilitate dispersal (in this case, standing vertically). Our study provides the first sound test of the function of what have been interpreted as dispersal-related behaviours of eriophyid mites. The low proportion of WCM exhibiting dispersal behaviour suggests there may be predisposed dispersers and residents in the population. Moreover, we found that WCM was generally more active than CRM, which is likely a contributing factor to its high invasive potential.

Eriophyoid mites (Eriophyoidea) are minute phytophagous mites with great economic importance and great invasive potential. In spite of their demonstrated impact on ecosystem functions, knowledge of eriophyoid mite fauna in the Arctic is lacking. To date, only eight eriophyoid mite species have been recorded from the entire region north of the Arctic Circle. The Svalbard archipelago is one of the most biologically investigated Arctic areas. Despite the fact that studies on invertebrates on Svalbard have been conducted for more than one hundred years, eriophyoids have never been recorded before from this place, except for one likely accidental record of a single specimen belonging to the genus Eriophyes. Thus, each new study of eriophyoid mite fauna in this region is important. In this paper, a new species of eriophyoid mite, Cecidophyes siedleckii n. sp., is described and illustrated. Nucleotide sequence data (D2 region of 28S rDNA) were employed to complement traditional morphological taxonomy. The first record of Aceria saxifragae (Rostrup 1900) from Svalbard is also provided, with supplementary morphological descriptions and illustrations. Eriophyoid mites represent an important and underutilized taxon that is available to ecologists studying the effects of changing climatic conditions on Svalbard.

Dry bulb mite (DBM), Aceria tulipae, is an economically important mite with a worldwide distribution and a broad host range. As a generalist, it is the most important eriophyoid mite attacking bulbous plants such as garlic, onion and tulip. To date, DBM has been recorded on host plants belonging to the families Liliaceae, Amaryllidaceae, Melanthiaceae and Asparagaceae. However, a precise understanding of DBM host range is lacking as it is largely based on casual records of mites on plants, some of which may include accidental hosts. Moreover, the possible existence of cryptic species has not been considered. In this study the hypothesis that DBM may be a complex of distinct genetic lineages or cryptic species was tested by comparing the common barcode sequence marker mtDNA COI of specimens from several populations originating from the Netherlands and Poland. The population growth rate of DBM on seven agriculturally important plant species and on various parts of the garlic plant was also experimentally assessed in the laboratory. The results did not support the first hypothesis, and indicated that DBM populations originating from Poland and the Netherlands shared essentially the same genome. In addition, they indicated that DBM reached the highest population growth rate on leek and also displayed high growth rates on garlic, chive and red onion, whereas white onion and wheat were not colonized by the mites. Answering the question of whether DBM is a single polyphagous species rather than a complex of cryptic lineages is of particular importance since the misidentification of pests may lead to ineffective control strategies. Moreover, improved knowledge of DBM host range is essential for assessing risk to crops.

Five new eriophyoid mite species (Eriophyidae) from Turkey are described and illustrated in this paper: Aceria vanensis n. sp., Aceria onosmae n. sp., Aculus lydii n. sp., Aculus gebeliae n. sp. and Aculus spectabilis n. sp.. The descriptions are based on the morphology of females collected from weedy plants, respectively: Amaranthus retroflexus L. (Amaranthaceae), Onosma isauricum Boiss. et Heldr. (Boraginaceae), Hypericum lydium Boiss. (Hypericaceae), Lotus gebelia Vent. (Fabaceae) and Stachys spectabilis Choisy ex DC. (Lamiaceae). The new species were found to be vagrant on their host plants with no visible damage symptoms observed.