Weevils - Entomological Society of Canada

Distribution. Manitoba to Alberta, south in the western United
States to Colorado. Alberta: Brooks, Cypress Hills, and Lethbridge.
Manitoba: Brandon, Ninette, and 5 miles southwest of Shilo.
Saskatchewan: Fort Walsh. "Great Bear." Willow. and 13 km west of
Tisdale.
Comments. This species is easily recognized, since it is the only
member of Apionidae with geniculate antennae (Fig. 19). The other
characters given in the key and the generic and species diagnosis also
help in recognizing this distinctive species. Specimens of this species
have been collected from alfalfa (Medicago satiua) fields in Alberta.
Genus Apion Herbst
Apion Herbst, 1797:100; Wagner 7910:7-67; Kissinger 1968:28;
O'Brien and Wibmer L982:20.
Kissinger (1968) provides 51 generic synonyms.
This is a large and extremely complex genus of over 300 North and
Central American species. Identifications to the specifrc level are very
difficult, the difficulty increased by the small size of specimens (usually
1.5-3.0 mm long) and by the lack of reliable, readily discernable
taxonomic characters. Correct identification is usually possible only if a
series of correctly determined specimens is available for comparison.
Canadian specimens are somewhat easier to identify, simply because the
number of species is much smaller.
Forty-five species are treated in the following key and discussions. A
number ofthese are not yet recorded in Canada, but they should occur in
the southern regions of this country.
The key that follows uses mostly male characters. Males are
distinguished from females by the shorter, more coarsely sculptured
rostrum and (sometimes) by an upward deflection of the last abdominal
sternite. Also, the last abdominal sternite of males is often notched at
the apex, making the tip of the last abdominal tergite visible.
Measurements are given from the anterior margin of the pronotum to
the elytral apex in dorsal view, head and rostrum excluded.
Description. Rostrum variable in length, cylindrical, filiform,
sometimes thick, straight to strongly curved, sometimes wedge- or
needle-shaped. Antennae straight; funicle with 7 segments; antennal
club generally oval or oblong. Eyes round or oval, weakly to strongly
convex. Pronotom variable, cylindrical, rounded laterally. Elytra oval or
oblong, more or less convex, wider than pronotum; sides broadly
rounded to elytral apex; striae usually punctured in regular rows;
interstria 9 often with 1 or 2 specialized setae. Pygidium covered by
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