Weevils - Entomological Society of Canada

Description. Length 1.7-2.7 mm. Body black, without bluish
reflection; antennae, legs, and tip of rostrum somewhat lighter. Head
quadrate, slightly longer than wide, with round, evenly spaced,
setiferous punctures; interpuncture spaces with dense, shining, minute
granules. Rostrum distinctly arcuate, about one-third longer than head
and pronotum; sides, in dorsal view, gradually diverging from antennal
insertion to apex, narrower at apex than frons; apex weakly flattened.
Antennae inserted near basal 0.2 (female) or just in front of basal 0.2
(male) of rostrum. Pronotum slightly longer than wide, widest behind
middle; sides slightly converging anteriorly; disc with round to
irregular, dense, setiferous punctures; interpuncture spaces with a few
granules. Elytra more than twice as long as wide, twice as wide as
pronotum; striae not impressed, with deep, quadrate punctures;
interstriae about half as wide (or less) as striae, weakly convex, each
with l row of small, round, setiferous punctures. Pygidium nearly
completely visible, covered by elytra only at extreme base.
Distribution. Prince Edward Island to Ontario, south through
the northeastern United States to Georgia, west to Kansas. New
Brunswick: Penobsquis. Nova Scotia: Halifax. Ontario: Toronto. Prince
Edward Island: Brackley Beach. Quebec: Kazabazta and Laniel.
Comments. See the key for characters to distinguish adults of
this species from those of P. cyanellus. The two Canadian representatives
of this genus are so dissimilar that further comparisons are unnecessary.
Hamilton (1983o) provides the following data on the life history of this
species in Ohio. His observations are probably valid for southern
Ontario. Adults feed on the leaves of sweet fern (Comptonia peregrina)
by scraping off strips of the upper epidermis. Larvae feed and develop in
leaf primordia, which have been cut from the host plant by the females.
Adults emerge in late May and do not live much beyond the end of June.
Females oviposit in and cut leaf primordia throughout June. Eggs hatch
in about 10 days, and larvae develop slowly, not reaching the fourth
instar until September. Winter is passed in the fourth-instar larval
stage. Spring pupation occurs within the hollowed-out leaf primordia in
mid to late May. One generation occurs each year. Hamilton (1983o)
provides illustrations and descriptions for the larvae and pupae of this
species.
Genus Merhynchifes Sharp
Merhynchites Sharp, 1889:57; Hamilton 1969:255; O'Brien and
Wibmer 1982 :L6; Hamilton 1985 : 49-64.
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