Microctonus melanopus (Ruthe) (Hymenoptera: Braconidae), a Parasitoid of Adult Cabbage Seedpod Weevil (Coleoptera: Curculionidae): Distribution in Southern Alberta and Female Diagnosis

2004 ◽  
Vol 39 (3) ◽  
pp. 350-361 ◽  
Author(s):  
Andrew S. Fox ◽  
Scott R. Shaw ◽  
Lloyd M. Dosdall ◽  
Byron Lee
Keyword(s):  
British Columbia ◽  
North America ◽  
Oilseed Crop ◽  
Brassica Napus L ◽  
Canadian Prairies ◽  
Ceutorhynchus Obstrictus ◽  
Southern Alberta ◽  
Cabbage Seedpod Weevil ◽  
Substantial Control ◽  
North America North

Microctonus melanopus (Ruthe) were reared and dissected from adult cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham), collected in southern Alberta in 2000 and 2001, and M. melanopus females were collected near Creston, British Columbia in 2001. These collections represent the first records for this European species in Canada. Previously published records of M. melanopus in North America are from the northwestern United States. A first diagnosis for adult female M. melanopus is provided that places M. melanopus in Loan's (1969) key for Microctonus species of North America, north of Mexico. Scanning electron photomicrographs of female morphology are provided to illustrate important diagnostic characters: the mesonotal sculpture with a distinct median longitudinal carina posteriorly, and the sculpture of metasomal tergite 1 with costae distinctly converging posteriorly. It is probable that M. melanopus has long been established in the southern interior of British Columbia because its host, C. obstrictus, has occurred there for many years. The occurrence of M. melanopus in southern Alberta is likely more recent, as its host only recently dispersed to that region. Rates of parasitism of C. obstrictus by M. melanopus, with one exception, were low in southern Alberta (<10%), and only one parasitized weevil was found on spring-seeded Brassica napus L., the primary brassicaceous oilseed crop associated with the weevil on the Canadian prairies. We hypothesize that M. melanopus will not provide substantial control of C. obstrictus in the mixed grassland ecoregion of its new range.

The species of Chalcidoidea (Hymenoptera) introduced to North America for biological control of the cabbage seedpod weevil, and the first recovery of Stenomalina gracilis (Chalcidoidea: Pteromalidae)

2006 ◽  
Vol 138 (3) ◽  
pp. 285-291 ◽  
Author(s):  
Gary A.P. Gibson ◽  
David R. Gillespie ◽  
Lloyd Dosdall
Keyword(s):  
Biological Control ◽  
British Columbia ◽  
North America ◽  
Classical Biological Control ◽  
Ceutorhynchus Obstrictus ◽  
Pteromalus Puparum ◽  
Cabbage Seedpod Weevil

AbstractThe species of Pteromalidae (Chalcidoidea) introduced to British Columbia, Canada, from Europe in 1949 as Trichomalus fasciatus (Thomson, 1878), Xenocrepis pura Mayr, 1904, and Habrocytus sp. for classical biological control of Ceutorhynchus obstrictus (Marsham, 1802) (Coleoptera: Curculionidae) are shown to be misidentifications of Trichomalus perfectus (Walker, 1835), Mesopolobus morys (Walker, 1848), and Stenomalina gracilis (Walker, 1834), respectively. Species reared subsequently from seedpods of Brassica spp. (Brassicaceae) in British Columbia and reported in the literature under the first three names are shown to be misidentifications of, respectively, Trichomalus lucidus (Walker, 1835), Mesopolobus moryoides Gibson, 2005, and one or both of Pteromalus puparum (L., 1758) and T. lucidus. There is no evidence that either T. perfectus or M. morys established in North America, but S. gracilis is newly recorded from southern British Columbia based on specimens reared from Brassicaceae seedpods in 2004 and 2005.

scholarly journals Larval phenologies and parasitoids of two seed-feeding weevils associated with hoary cress and shepherd's purse (Brassicaceae) in Europe

2011 ◽  
Vol 143 (4) ◽  
pp. 399-410 ◽  
Author(s):  
Franck J. Muller ◽  
Lloyd M. Dosdall ◽  
Peter G. Mason ◽  
Ulrich Kuhlmann
Keyword(s):  
Biological Control ◽  
Brassica Napus ◽  
North America ◽  
Host Specificity ◽  
Brassica Rapa ◽  
Ceutorhynchus Obstrictus ◽  
Hoary Cress ◽  
Cabbage Seedpod Weevil ◽  
Alien Pest ◽  
Host Associations

AbstractIn Europe, Ceutorhynchus turbatus Schultze and Ceutorhynchus typhae (Herbst) (Coleoptera: Curculionidae) feed on seeds from hoary cress and shepherd's purse (Cardaria draba (L.) Desv. and Capsella bursa-pastoris (L.) Medik.); both plants are invasive in North America. In North America, C. turbatus is a candidate for biological control of hoary cress, C. typhae is adventive, and both are sympatric with cabbage seedpod weevil (Ceutorhynchus obstrictus (Marsham)), an invasive alien pest of canola (Brassica napus L. and Brassica rapa L., Brassicaceae). We investigated host associations among C. turbatus, C. typhae, and their parasitoids in Europe. Of particular interest was host specificity of Trichomalus perfectus (Walker) and Mesopolobus morys (Walker) (Hymenoptera: Pteromalidae), candidates for biological control of C. obstrictus in North America. We found no evidence that T. perfectus attacks C. turbatus or C. typhae; however, M. morys was the most common parasitoid associated with C. turbatus.

scholarly journals A review of the species of Mesopolobus (Chalcidoidea: Pteromalidae) associated with Ceutorhynchus (Coleoptera: Curculionidae) host-species of European origin

2007 ◽  
Vol 97 (4) ◽  
pp. 387-397 ◽  
Author(s):  
H. Baur ◽  
F.J. Muller ◽  
G.A.P. Gibson ◽  
P.G. Mason ◽  
U. Kuhlmann
Keyword(s):  
Biological Control ◽  
North America ◽  
Classical Biological Control ◽  
Junior Synonym ◽  
European Origin ◽  
Ceutorhynchus Obstrictus ◽  
Hoary Cress ◽  
Cabbage Seedpod Weevil ◽  
Lepidium Draba ◽  
First Time

AbstractFour species of Mesopolobus Westwood were reared as parasitoids of Ceutorhynchinae hosts in Europe during surveys in 2000–2004. An illustrated key is given to differentiate the four species, M. gemellus Baur & Muller sp. n., M. incultus (Walker), M. morys (Walker) and M. trasullus (Walker), plus M. moryoides Gibson, a parasitoid of the cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham), in North America. Pteromalus clavicornis Walker is recognized as a junior synonym of M. incultussyn. n., and Pteromalus berecynthos Walker (also a junior synonym of M. incultus) is considered a correct original spelling. For Disema pallipes Förster (a junior synonym of Mesopolobus morys), a lectotype is designated. Mesopolobus morys is for the first time accurately associated with the seed weevil Ceutorhynchus turbatus (Schultze), a potential agent for classical biological control, of hoary cress, Lepidium draba L. (Brassicaceae), in North America. Mesopolobus gemellus is associated with another seed weevil, Ceutorhynchus typhae (=C. floralis) (Herbst), in pods of shepherd's purse, Capsella bursa-pastoris (L.) Medik. (Brassicaceae). Implications of the host–parasitoid associations are discussed relative to the introduction of species to North America for classical biological control of the cabbage seedpod weevil.

Reproductive Biology of Ceutorhynchus obstrictus (Coleoptera: Curculionidae) on Wild and Cultivated Brassicaceae in Southern Alberta

2003 ◽  
Vol 38 (4) ◽  
pp. 533-544 ◽  
Author(s):  
Andrew S. Fox ◽  
Lloyd M. Dosdall
Keyword(s):  
Wide Distribution ◽  
Ovary Development ◽  
Infestation Level ◽  
Apparent Discrepancy ◽  
Brassica Napus L ◽  
Early Season ◽  
Ceutorhynchus Obstrictus ◽  
Wild Host ◽  
Southern Alberta ◽  
Pan Traps

Mated and gravid status were assessed for early-season populations of Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae) on wild and cultivated Brassicaceae in southern Alberta, Canada. Mated female C. obstrictus were found in the first samples examined (22 May 2001). At least 84% of C. obstrictus dispersing to wild host sites up to 23 May 2001 (captured using yellow pan traps) were males. Females of C. obstrictus with at least one egg in the lateral oviducts were first encountered on 6, 8 and 18 June 2001 on Descurainia sophia (L.) Webb, Sinapis arvensis L., and Cardaria spp., (Brassicaceae), respectively. Females on S. arvensis, a true host with pods that can sustain larvae, had more robust ovary development than females on Cardaria spp. and D. sophia, food hosts with pods that cannot sustain larvae. The most fecund sample (n = 30) from S. arvensis was collected on 24 June 2001 when 80% of females had a mean of 7.2 ± 2.7 (±SD) eggs in the lateral oviducts. The most fecund full samples (n = 30) from Cardaria spp. and D. sophia had 6.7% and 40.0%, respectively, of females with at least one egg in the lateral oviducts, and an overall maximum of four eggs in the lateral oviducts per female. There is no apparent reproductive advantage to C. obstrictus in developing eggs on early-season food hosts, although food hosts likely play an important role in sustaining C. obstrictus until true hosts are encountered. Although gravid status was high in females on S. arvensis, this host supported relatively few larvae. The highest infestation level of C. obstrictus per sample of S. arvensis pods in 2001 was 13.5% (n = 891 pods) based on the presence of eggs, larvae, and exit holes. A sample of volunteer Brassica napus L. (Brassicaceae) pods (n = 100) had a 77% infestation level. The apparent discrepancy between the relatively robust gravid status of C. obstrictus on S. arvensis, and low pod infestation, was explained as a combination of factors that likely include an inherent unsuitability of wild S. arvensis pods for C. obstrictus. However, given the wide distribution of S. arvensis in southern Alberta, this wild true host would likely maintain low populations of C. obstrictus in the absence of volunteer and spring-seeded cultivated hosts.

scholarly journals On the misidentification of chalcid (Hymenoptera: Chalcidoidea) parasitoids of the cabbage seedpod weevil (Coleoptera: Curculionidae) in North America

2005 ◽  
Vol 137 (4) ◽  
pp. 381-403 ◽  
Author(s):  
Gary A.P. Gibson ◽  
Hannes Baur ◽  
Bryan Ulmer ◽  
Lloyd Dosdall ◽  
Franck Muller
Keyword(s):  
North America ◽  
Similar Species ◽  
Ceutorhynchus Obstrictus ◽  
Cabbage Seedpod Weevil ◽  
Scanning Electron

AbstractPrevious identifications in North America of Trichomalus perfectus (Walker, 1835) and Mesopolobus morys (Walker, 1848) (Chalcidoidea: Pteromalidae), the principal chalcid parasitoids of the cabbage seedpod weevil (Ceutorhynchus obstrictus Marsham, 1802) in Europe, are shown to be misidentifications of Trichomalus lucidus (Walker, 1835) and Mesopolobus (Xenocrepis) moryoidessp. nov., respectively. Necremnus duplicatus Gahan, 1941 (Chalcidoidea: Eulophidae) is synonymized formally under Necremnus tidius (Walker, 1839) syn. nov., confirming a previous, tentative synonymy. Both sexes of N. tidius, M. moryoides, and T. lucidus are illustrated and compared with those of similar species using macrophotography and scanning electron microphotography. Hypotheses are offered to explain why the principal chalcid parasitoids of the cabbage seedpod weevil differ between North America and Europe and how the three treated species came to be in North America.

Foliicolous bryophytes and lichens of Thuja plicata in western British Columbia

1973 ◽  
Vol 51 (3) ◽  
pp. 571-580 ◽  
Author(s):  
Dale H. Vitt ◽  
Michael Ostafichuk ◽  
Irwin M. Brodo
Keyword(s):  
United States ◽  
British Columbia ◽  
North America ◽  
Southeastern United States ◽  
Thuja Plicata ◽  
First Report ◽  
Northwestern North America ◽  
North America North ◽  
Lichen Flora

Four species of mosses, all in the genus Orthotrichum; 1 species of hepatics; and 16 species of lichens compose the foliicolous bryophyte and lichen flora of Thuja plicata L. leaves in certain areas of western British Columbia. This is the first report of foliicolous mosses and hepatics for North America, north of the tropical and subtropical regions of the southeastern United States. The taxonomy of the four species of Orthotrichum is discussed and a key given differentiating the species.All of the species that have been found on Thuja leaves except perhaps Catillaria bouteillei are facultative foliicolous species and occur on leaves, only in scattered areas of northwestern North America. Two taxa of lichens, Catillaria bouteillei (Desm.) Zahlbr. and Cetrelia cetrarioides (Del. ex Duby) W. Culb. & C. Culb. (perlatolic acid strain) are reported as new to Canada.

Cabbage seedpod weevil (Coleoptera: Curculionidae): new pest of canola in northeastern North America

2001 ◽  
Vol 133 (5) ◽  
pp. 709-711 ◽  
Author(s):  
Jacques Brodeur ◽  
Luc-André Leclerc ◽  
Marc Fournier ◽  
Michèle Roy
Keyword(s):  
North America ◽  
Seed Germination ◽  
Seed Weight ◽  
Oil Content ◽  
Yield Losses ◽  
Northeastern North America ◽  
Ceutorhynchus Obstrictus ◽  
Cabbage Seedpod Weevil ◽  
Cruciferous Plants ◽  
New Pest

The cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham) [= C. assimilis (Paykull)] (Colonnelli 1993), is a univoltine species native to Europe that feeds on canola and other oilseed cruciferous plants. The adult overwinters in debris and soil outside fields and colonizes canola at the blooming stage (Dosdall et al. 2001). Eggs are laid singly into the immature pods and each larva consumes five to seven seeds before cutting a hole in the pod to wriggle out and pupate in the soil (Dmoch 1965). Yield losses are difficult to assess because the plant compensates for bud and pod injuries caused by insects or pathogens (Lamb 1989). Nevertheless, pod feeding by larvae causes much damage, as canola yields can be reduced from 15 to 35% (Homan and McCaffrey 1993). Feeding by adults can also be significant, as it can reduce oil content, seed weight, and seed germination (Buntin et al. 1995).

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