02079nas a2200181   4500008004100000020001400041245013500055210006900190260001200259300001000271490000700281520139700288653001901685100001901704700001801723700002101741856013501762       2007                        eng d  a0031-060300aStudies on the biology of the gorse seed weevil, Exapion ulicis (Forster 1771), in Northern California (Coleoptera: Curculionidae)0 aStudies on the biology of the gorse seed weevil Exapion ulicis F  cJanuary  a32-400 v833 aThe seed weevil, Exapion ulicis (Forster 1771), was released in northern California as a biological control agent against gorse, an exotic shrub that invades grasslands and wildlands in the coastal counties of California. Several studies were conducted to examine the relationship between egg maturation and deposition with the flowering phenology of its host plant. Female weevils fed different diets of flowers and foliage showed significant differences in ovarian development. Females relied on their stored fat reserves to sustain them through the winter season. Stored fat in newly emerged females was 21% in June or July, declining to 10% by late January the following year. Fat maintenance was sustained throughout the ovipositional period by both flower and foliage feeding. The results show that the biology and life cycle of this weevil was closely tied to the production of flowers by gorse. Oviposition was synchronized with anthesis and flower feeding in March (early spring). Larval development occurred in late March through mid-May and adult emergence began in early M ay. Larval consumption of seeds was the primary means of feeding damage. When present, larval feeding reduced seed number per pod between 64% and 87%. Infestation of seedpods by weevils varied from 4% (late March) to 71% (early June) and translated to a population-level estimate of seed destruction of 51%.10aExapion ulicis1 aMaddox, D., M.1 aJoley, D., B.1 aPitcairn, M., J.  uhttps://weevil.myspecies.info/studies-biology-gorse-seed-weevil-exapion-ulicis-forster-1771-northern-california-coleoptera-curcu-002079nas a2200181   4500008004100000020001400041245013500055210006900190260001200259300001000271490000700281520139700288653001901685100001901704700001801723700002101741856013501762       2007                        eng d  a0031-060300aStudies on the biology of the gorse seed weevil, Exapion ulicis (Forster 1771), in Northern California (Coleoptera: Curculionidae)0 aStudies on the biology of the gorse seed weevil Exapion ulicis F  cJanuary  a32-400 v833 aThe seed weevil, Exapion ulicis (Forster 1771), was released in northern California as a biological control agent against gorse, an exotic shrub that invades grasslands and wildlands in the coastal counties of California. Several studies were conducted to examine the relationship between egg maturation and deposition with the flowering phenology of its host plant. Female weevils fed different diets of flowers and foliage showed significant differences in ovarian development. Females relied on their stored fat reserves to sustain them through the winter season. Stored fat in newly emerged females was 21% in June or July, declining to 10% by late January the following year. Fat maintenance was sustained throughout the ovipositional period by both flower and foliage feeding. The results show that the biology and life cycle of this weevil was closely tied to the production of flowers by gorse. Oviposition was synchronized with anthesis and flower feeding in March (early spring). Larval development occurred in late March through mid-May and adult emergence began in early M ay. Larval consumption of seeds was the primary means of feeding damage. When present, larval feeding reduced seed number per pod between 64% and 87%. Infestation of seedpods by weevils varied from 4% (late March) to 71% (early June) and translated to a population-level estimate of seed destruction of 51%.10aExapion ulicis1 aMaddox, D., M.1 aJoley, D., B.1 aPitcairn, M., J.  uhttps://weevil.myspecies.info/studies-biology-gorse-seed-weevil-exapion-ulicis-forster-1771-northern-california-coleoptera-curculi02044nas a2200181   4500008004500000020001400045245010900059210006900168260001000237300001000247490000700257520139700264653001901661100002201680700002101702700002101723856011801744       2008                        Engldsh    a1049-964400aThe phenology and impact of the gorse seed weevil, Exapion ulicis, on gorse, Ulex europaeus, in Tasmania0 aphenology and impact of the gorse seed weevil Exapion ulicis on   cApril  a85-920 v453 aThe patterns of gorse pod production, the phenology of Exapion ulicis and its impact on gorse seed production were assessed ill a field study conducted at two sites over 20 months in Tasmania, Australia. The production of gorse pods varied considerably between the two sites as did the impact of E. ulicis on mature gorse seed production. At Stonehenge, a site in Tasmania's eastern midlands, green pods were produced in spring and summer and black pods were produced in late spring, summer and early autumn, the timing of which was well synchronised with E. ulicis seed feeding activity. At Lymington, a coastal site in southern Tasmania, both green and black pods were produced almost all year, the timing of which was not well synchronised with E ulicis seed feeding activity. As a result, the average percentage of mature seeds that were damaged by E ulicis was 2.7 times higher at Stonehenge (45.5%) than at Lymington (16.7%). These levels of seed destruction were much lower than the levels (i.e. 75-85%) that were considered necessary by previous workers to cause a decline in gorse densities. The results show that additional agents are needed to act in combination with E. ulicis and reduce seed production further if seed feeding biological control agents are to have an impact on plant densities in Tasmanian gorse populations. ([copyright]) 2008 Elsevier Inc. All rights reserved.10aExapion ulicis1 aDavies, Jamie, T.1 aIreson, John, E.1 aAllen, Geoff, R.  uhttps://weevil.myspecies.info/phenology-and-impact-gorse-seed-weevil-exapion-ulicis-gorse-ulex-europaeus-tasmania02350nas a2200193   4500008004500000020001400045245010600059210006900165260000900234300001200243490000700255520167200262653002401934653001901958100001801977700002101995700001602016856012402032       2008                        Engldsh    a0307-694600aGenetic divergence and ecological specialisation of seed weevils (Exapion spp.) on gorses (Ulex spp.)0 aGenetic divergence and ecological specialisation of seed weevils  cJune  a328-3360 v333 a1. Reproductive isolation of sympatric populations may result from divergent selection of populations in different environments, and lead to ecological specialisation. In Brittany (France), the gorse Ulex europaeus (Fabaceae, Genisteae), may be encountered in sympatry with one of the two other gorse species present: U. gallii and U. minor. A recent study based on morphological identification of seed predators of gorse has shown that two weevil species (Curculionoidea, Apionidae) infest gorse pods at different seasons and have different host ranges: Exapion ulicis infests U. europaeus in spring, whereas E. lemovicinum infests U. gallii and U. minor in autumn. Weevil populations may thus have diverged in sympatry.2. As morphological identification of weevils is often difficult and some of the characters used may exhibit individual or environmental variation, mitochondrial and nuclear sequences of weevils collected within pods of the three gorse species in 10 populations of Brittany were used to reconstruct their phylogeny.3. The results reveal that species differentiation based on morphological characters is confirmed by the two molecular data sets, showing that E. ulicis and E. lemovicinum are distinct species, and suggesting the absence of host races. Finally, E. ulicis was able to use U. gallii and U. minor pods in spring in some years in some populations, which appeared to depend on the availability of pods present during its reproductive period.4. Divergence between E. ulicis and E. lemovicinum may have resulted from temporal isolation of reproductive periods of weevil populations followed by specialisation of insects to host phenology.10aExapion lemovicinum10aExapion ulicis1 aBarat, Myriam1 aTarayre, Michele1 aAtlan, Anne  uhttps://weevil.myspecies.info/genetic-divergence-and-ecological-specialisation-seed-weevils-exapion-spp-gorses-ulex-spp01977nas a2200193   4500008004100000020001400041245012500055210006900180260001300249300001200262490000700274520127200281653001901553100001801572700002101590700002101611700001601632856013501648       2010                        eng d  a0022-191000aOverwintering strategy of two weevils infesting three gorse species: When cold hardiness meets plant-insect interactions0 aOverwintering strategy of two weevils infesting three gorse spec  cFebruary  a170-1770 v563 aThe cold hardiness of two closely related weevil species, Exapion ulicis and E. lemovicinum was studied in relation to their life cycles. These two seed-eating weevils reproduce on Ulex plant species with different fruiting phenologies. E. ulicis lays eggs in spring and overwinters as an adult while E. lemovicinum lays eggs in autumn and overwinters as a larva. Adult weevils were collected in natural populations of Brittany (Western France) and characterized with morphological and molecular tools before experiments. We showed that both weevil species exhibited low supercooling points (SCPs) with mean seasonal values below -17 [degree]C. Fresh mass, moisture content and sex were not correlated to supercooling ability. Weevils died upon freezing and the lower lethal temperatures (LLT) were within the range of SCP, indicating that both species are freezing intolerant. Comparison between species for SCP, LLT and survival to exposure at -8 [degree]C in winter showed a higher cold resistance for E. ulicis than for E. lemovicinum. In addition, the seasonal evolution of cold hardiness differed depending on the species. These features suggest that response to cold of weevils is linked to their life cycles, and thus to the life history of their host plants.10aExapion ulicis1 aBarat, Myriam1 aVernon, Philippe1 aTarayre, Michele1 aAtlan, Anne  uhttps://weevil.myspecies.info/overwintering-strategy-two-weevils-infesting-three-gorse-species-when-cold-hardiness-meets-plant-ins02120nas a2200193   4500008004100000020001400041245010100055210006900156260001100225300001200236490000800248520144700256653002401703653001901727100001801746700002101764700001601785856012501801       2007                        eng d  a0013-870300aPlant phenology and seed predation: interactions between gorses and weevils in Brittany (France)0 aPlant phenology and seed predation interactions between gorses a  cAugust  a167-1760 v1243 aExapion ulicis (Forster) and Exapion lemovicinum (Hoffmann) (Coleoptera: Curculionoidea: Apionidae) are seed predators of the three gorse species occurring in Brittany (France): Ulex europaeus L., Ulex gallii Planch., and Ulex minor Roth. (Fabaceae). Host-plant phenology plays a major role in the relationship between apionid weevils and their gorse species, because larvae develop within gorse pods and adults have to wait for pod dehiscence to be released. We monitored flowering and fruiting phenology of gorse species, weevil reproductive behaviour, and egg-laying patterns in six natural populations in the native area of these gorse species. At each site, U. europacus, which flowers mainly in spring, was sympatric with one of two autumn flowering gorse species, U. gallii and U. minor. We noticed that E. ulicis laid eggs in spring and was restricted to U. europaeus whereas E. lemovicinum laid eggs in autumn and was restricted to the two autumn-flowering species U. gallii and U. minor. Therefore, host specificity depended on gorse phenology, and not on geographic proximity. In addition, the infested pod content showed that E. ulicis laid several eggs per pod and suggested that females chose pods with the highest numbers of seeds. In contrast, E. lemovicinum laid a single egg per pod and showed no preference for pods with many seeds. Finally, the impact of seed predation by E. ulicis was higher than that of E. lemovicinum.10aExapion lemovicinum10aExapion ulicis1 aBarat, Myriam1 aTarayre, Michele1 aAtlan, Anne  uhttps://weevil.myspecies.info/plant-phenology-and-seed-predation-interactions-between-gorses-and-weevils-brittany-france