This study recorded distribution and size of alfalfa weevil (Hypera postica (Gyllenhal); Coleoptera: Curculionidae) populations in Saskatchewan, Canada, from 2001 to 2014. The spread of alfalfa weevil across the province, originally southwest to southeast, was northward and westward during this time. By 2014, only northwestern and west central areas remained relatively alfalfa weevil free. From a minor pest in 2001, the alfalfa weevil increased to be the principal insect pest of alfalfa (Medicago sativa Linnaeus; Fabaceae) in 2014. The parasitoid Bathyplectes curculionis (Thomson) (Hymenoptera: Ichneumonidae) had a similar distribution. Other parasitoids collected included Oomyzus incertus (Ratzeburg) (Hymenoptera: Eulophidae) and Microctonus colesi Drea (Hymenoptera: Braconidae). Conservation of these parasitoids is an important step in maximising their effectiveness as alfalfa weevil biocontrol agents. Molecular sequencing of the DNA barcoding region of specimens identified morphologically as B. curculionis indicated moderately high levels of sequence divergence among specimens (up to 5.8%); however, interspecific genetic variation between other species of Bathyplectes Förster was also high. Therefore, we conclude that B. curculionis was the only Bathyplectes species collected in our study. An illustrated key to the described species of Bathyplectes in North America is provided, as well as DNA barcodes of most species, including five distinct barcodes in the Bathyplectes curculionis–B. exiguus (Gravenhorst) species complex.

这项研究记录了2001年至2014年加拿大萨斯喀彻温省的苜蓿象鼻虫（Hypera postica（Gyllenhal）；鞘翅目：Curculionidae）种群的分布和大小。苜蓿象鼻虫在全省的分布，最初是西南向东南，在此期间向北和向西这次。到2014年，只有西北和西部中部地区仍然没有相对苜蓿象鼻虫。苜蓿象鼻虫从2001年的次要害虫增加到2014年成为苜蓿的主要害虫（苜蓿（Medicago sativa Linnaeus； Fabaceae））。寄生性拟南芥（Thomson）（膜翅目：Ichneumonidae）的分布相似。收集到的其他寄生虫包括不合格卵（Oomyzus incertus，拉特堡）（膜翅目：Eulophidae）和Microctonus colesi Drea（膜翅目：Braconidae）。这些寄生物的保存是使它们作为苜蓿象鼻生物防治剂的效力最大化的重要步骤。在形态学上被鉴定为库克氏梭菌的标本的DNA条形码区域的分子测序表明标本之间的序列差异水平适中（最高5.8％）；然而，其他BathyplectesFörster物种之间的种间遗传变异也很高。因此，我们得出的结论是，curculionis芽孢杆菌是我们研究中唯一收集到的Bathyplectes物种。所描述的Bath虫物种的插图钥匙提供了北美地区的信息，以及大多数物种的DNA条码，其中包括Bathyplectes curculionis – B. exiguus（Gravenhorst）物种群中的五个不同的条码。