Weevils - Entomological Society of Canada

sparser toward tip. Rostrum of female 1.3-1.6 times longer than
pronotum, similar to male, except scales below antennal insertion finer
and sparser. Antennae inserted between basal 0.3 (male) or 0.2-0.3
(female) of rostrum. Eye slightly convex. Pronotum at base l.I-L2
times wider than long; sides slightly diverging to near basal third,
rounding to slightly constricted apex, lacking basal flange; disc
moderately convex, with moderately deep punctures bearing fine scales,
these sometimes lying transversely toward median line of pronotum;
interpuncture spaces finely alutaceous. Elytra L.2-7. times longer than
wide; striae fine, moderately deeply impressed, bearing scales slightly
coarser then scales on pronotum; interstriae flat, about 3.0 times wider
than striae, each with 1 or 2 partly confused rows of fine punctures
bearing scales like those on striae; interstriae 7 and 9 each with 1 long
specialized seta. Tarsal claw in males with acute basal tooth.
Distribution. Manitoba to Alberta, south throughout the
western half of the United States to Baja California, Mexico. Alberta:
Medicine Hat and Scandia. Manitoba: Aweme, 2 miles east of Douglas,
and Ninette.
Comments. This species is placed in the subgenus Pseudapion
and is probably best distinguished by the characters summarized in the
key. Kissinger (1968) states that the species is complex. At least two
distinct populations exist in the United States and Canada. One
population occurs in Texas, Arizona, Utah, and Oklahoma, whereas the
other is widespread from Canada to Texas. This latter population occurs
sympatrically at various points with A. capitone and tends to have the
front femur comparatively stout. This character helps to distinguish
sympatric males ofA. anlclurutn from those of A. capitone. In addition, in
males of A. amaurum the anterior margin of the antennal scrobe is
situated at a distance in front of the eye distinctly less than the
maximum width of femur 1in profile, whereas in males of A. capitonethe
same measurement is equal to or greater than the width of femur 1.
Nothing is known of the life history of this species. The Canadian host is
unrecorded. Specimens have been collected from prairie clover
(Petalostemoz species) and Mimosa borealis in Mexico and United
States. Salsbury (1984) records this species from Dalea aurea and
Petalostemon candidus in Kansas.
Apion antennatum Smith
Figs. 59, 60, Map 12
Apion antennatum Smith, 1884:53 (lectotype, California; USNM);
Kissinger 7968:248; Hatch 1971:331; O'Brien and Wibmer 1982:20.
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