| growth and development of larvae and galls of urophora cardui (diptera, tephritidae) on cirsium arvense (compositae). | the tephritid fly urophora cardui induces a large multi-chambered gall within the stems of cirsium arvense. three distinct phases of gall development have been identified as initiation, growth, and maturation. during initiation the insect gains control of tissue development and during the gall's growth phase parenchyma cells proliferate rapidly surrounding the larvae with thick layers of cells. patches of primary nutritive cells appear along the surface of larval chambers during the growth phase ... | 1985 | 28310661 |
| the problem of optimal clutch size in a tritrophic system: the oviposition strategy of the thistle gallfly urophora cardui (diptera, tephritidae). | the problem of optimal clutch sizes is a central theme in life history theory. optimal allocation of eggs is especially complicated for insects in tritrophic systems. in this study we analyze some of the processes determining clutch sizes of the thistle gallfly urophora cardui, a monophagous tephritid fly associated with cirsium arvense. u. cardui forms multilocular shoot galls, which vary broadly in their size and number of their gall cells. we investigate various fitness consequences of gall s ... | 1996 | 28307842 |
| characterisation of microsatellite and snp markers from miseq and genotyping-by-sequencing data among parapatric urophora cardui (tephritidae) populations. | phylogeographic analyses of the gall fly urophora cardui have in earlier studies based on allozymes and mtdna identified small-scale, parapatrically diverged populations within an expanding western palearctic population. however, the low polymorphism of these markers prohibited an accurate delimitation of the evolutionary origin of the parapatric divergence. urophora cardui from the western palearctic have been introduced into canada as biological control agents of the host plant cirsium arvense ... | 2017 | 28828237 |
| tracing the history and ecological context of wolbachia double infection in a specialist host (urophora cardui)-parasitoid (eurytoma serratulae) system. | the endosymbiotic bacterium wolbachia is the most widespread bacteria in insects, yet the ecology of novel acquisitions in natural host populations is poorly understood. using temporal data separated by 12 years, i tested the hypothesis that immigration of a parasitoid wasp led to transmission of its wolbachia strain to its dipteran host, resulting in double-strain infection, and i used geographic and community surveys to explore the history of transmission in fly and parasitoid. double infectio ... | 2017 | 28168034 |
| clinal genetic variation and the 'rare allele phenomenon' in random mating populations of urophora cardui (diptera: tephritidae). | in the present study we investigate a contact zone between two population groups of the tephritid fly urophora cardui. we investigate scenarios that may have produced the genetic differentiation of the two groups, and we describe the 'rare allele phenomenon' from the contact zone. the rare allele phenomenon refers to alleles that are found at high frequency in contact zones but are rare or lacking outside the contact zone. the phenomenon is often observed in hybrid zones between subspecies of li ... | 2004 | 15609551 |