Robert S. Anderson. 1998. Weevils (Curculionoidea) in Smith, I.M., and G.G.E. Scudder, eds. Assessment of species diversity in the Montane Cordillera Ecozone. Burlington: Ecological Monitoring and Assessment Network, 1998.

WEEVILS (CURCULIONOIDEA)

(excluding Scolytidae, Platopodidae)

Robert S. Anderson
Research Division, Canadian Museum of Nature
P.O. Box 3443, Station D
Ottawa, Ontario
K1P 6P4

ABSTRACT

A total of 233 species in 80 genera of Curculionoidea (excluding Scoytidae) are recorded from the Montane Cordillera ecozone of western Canada. The families Nemonychidae (3; 6), Anthribidae (3; 4), Rhynchitidae (2; 3), Apionidae (1; 11) and Curculionidae (71; 209) are represented. This represents 80.6% of the 288 species of Curculionoidea (excluding Scoytidae) known from British Columbia.

Species with extensive distributions dominate the fauna; 73 species (31.3%) are widespread, 32 species (13.7%) are northern transcontinental, 53 species (22.7%) are western montane, 25 species (10.7%) are northern transcontinental/western montane, 25 species (10.7%) are western arid, and 16 species (6.9%) are western/central arid in distribution. An additional two species are found in the western montane region from British Columbia north into the Yukon Territory and Alaska and five species are endemic to British Columbia. Seventeen species (7.3%) of the fauna are introduced by humans and 24 species (10.3%) are Holarctic.

Habitat associations include montane conifer forest with 34 associated species (14.6%), montane transition habitat with 71 species (30.5%), alpine with two species, wetlands with 70 species (30.0%), and dry valleys with 44 species (18.9%). Eighteen weevils species (7.7%) are found in a variety of habitat types. Notable families of plants serving as hosts for weevils in the Montane Cordillera include Pinaceae, Salicaceae, Fabaceae, Cruciferae and Rosaceae.

In addition to thirteen species of weevils previously proposed as potentially rare and endangered within British Columbia, 20 species are proposed as new candidates for consideration for this status. Twenty two of the 33 species that are considered potentially rare and endangered are found in arid habitats, generally in the south Okanagan Basin. Habitat loss in this region is the greatest threat to conservation of species diversity of Curculionoidea in the Montane Cordillera ecozone but further studies and inventories within this region are needed to assess the actual taxonomic status and geographic distributions of these apparently rare species in Canada.

INTRODUCTION

The Curculionoidea or weevils are one of the most diverse clades of Coleoptera. Weevils are endopterygotes with complete metamorphosis. Adults are typical beetles with the front wings modified into protective elytra which cover the membranous hind wings which may be short and non-functional or even absent in some species. The most distinctive characteristic of nearly all adult weevils is the presence of a prolonged rostrum with the mouthparts situated at the apex. Immature stages of most species are legless and phytophagous; descriptions of immature stages and details of natural history are poorly known for most species.

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