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Two economically important eriophyoid mites, Aceria tosichella (wheat curl mite; WCM) and Aceria tulipae (dry bulb mite; DBM), were frequently confounded in the world literature until the late 20th Century. Their morphological similarity and ambiguous data from plant-transfer and virus-transmission trials contributed to this confusion. Until recently, there was a general lack of knowledge about the existence of species complexes and it was not possible to accurately genotype tested mites. In the present study, two WCM genotypes of divergent host specificity ( MT-1 and MT-2) and one DBM genotype were tested for the acceptance of Poaceae, Amarylidaceae, and Liliaceae species that were reported or suspected as hosts of WCM or DBM. The MT-1 lineage colonized all tested plants. Onion- and garlic-associated DBM populations did not colonize tulip and wild garlic, suggesting that host-acceptance variability exists within A. tulipae s.l. Morphometric analysis did not discriminate closely-related MT-1 and MT-2 genotypes but completely separated both WCM genotypes from DBM based on the larger overall body size of the latter. Three morphological traits combined to discriminate between the DBM and MT-1 genotypes, both of which can infest Amarylidaceae bulbs. In total, these combined DNA sequence, host-acceptance, morphometrical results unambiguously separated two WCM and one DBM genotypes. Similar studies on additional lineages of both WCM and DBM should ultimately dispel previous taxonomic confusion between these two species. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111, 421-436. [ABSTRACT FROM AUTHOR]

Aceria tosichella (the wheat curl mite, WCM) is a global pest of wheat and other cereals, causing losses by direct damage, as well as the transmission of plant viruses. The mite is considered to have an unusually wide host range for an eriophyoid species. The present study tested the commonly held assumption that WCM is a single, highly polyphagous species by assessing the host range of genetically distinct lineages of WCM occurring in Poland on different host plants. Genotyping was performed by analyzing nucleotide sequence data from fragments of the mitochondrial cytochrome c oxidase subunit I ( COI) and the nuclear D2 region of 28 S rDNA. Mean between-lineage distance estimated using COI data was found to be one order of magnitude greater than the within-clade lineage and, in some cases, comparable to distances between WCM lineages and a congeneric outgroup species. Host acceptance was tested by quantifying population growth for different WCM mitochondrial ( mt)DNA lineages when transferred from source host plants to test plants. These experiments revealed significant differences in host colonization ability between mt DNA lineages, ranging from highly polyphagous to more host-specific. The present study reveals that WCM is composed of several discrete genetic lineages with divergent host-acceptance and specificity traits. Genetic variation for host acceptance within A. tosichella s.l. may act as a reproductive barrier between these lineages, most of which had narrow host ranges. Two lineages appear to have high pest potential on cereals, whereas several others appear to specialize on wild grass species. We conclude that WCM is not a homogeneous species comprising polyphagous panmictic populations rather it is a complex of genetically distinct lineages with variable host ranges and therefore variable pest potential. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109, 165-180. [ABSTRACT FROM AUTHOR]