|scientific name Byrrhus cyclophorus |
Adults are found in mosses, moist sand or soil and under logs, bark and stones (El-Moursy 1961).
Adults fly in spring and early summer (Johnson 2000) and have been collected in Alberta in May.
Length greater than 6.5 mm. Body form oval, convex, blackish-piceous (Casey 1912) with fine ash-coloured pubescence (Downie et al. 1996). This species is closely related to B. americanus and has similar elytral markings except outer black vitta (longitudinal stripe) represented by 2 or 3 small indiscernible spots (El-Moursy 1970 and LeConte 1854). Labrum triangular (El-Moursy 1970) and the last joint of the palpi oval and less truncate than B. americanus (LeConte 1854). Antennomeres 1 and 11 darker (Downie et al. 1996). Pronotum and elytra sparsely and finely microreticulate (Johnson 1991). Pronotal punctures small and well separated by spaces greater than own diameter; punctures on frons large and shallow while punctures on elytra are deep (Johnson 1991). Male genitalia with median lobe bluntly pointed at apex and parameres with apices rounded (El-Moursy 1970). Female genitalia presently unidentifiable (Hatch 1961). Larvae with large hypognathous head (head and mouth directed ventrally) with distinctive ventral epicranial ridges and 6 stemmata. Similar in body form to larvae of Chrysomelidae but with noticeable lacinia and articulated galea (LeConte 1854).
Adults may occasionally be found in the soil of seedlings in nurseries (Lawrence 1991 and Lawrence et al. 2000) and sometimes as washup or windblown drift on beaches (Johnson 200). Larvae burrow under moss and underlying substrate (Johnson 2000). When disturbed, adults pull in their appendages and remain motionless. This behaviour creates the appearance of a small pebble or pill, hence the common name (El-Moursy 1961).
Relatively common in Alberta.
Both adults and larvae are herbivorous on the leaves and rhizoids of mosses and liverworts (El-Moursy 1961 and Lawrence et al. 2000).
This species is recorded from the southern half of Alberta. The range of these beetles is confined to western North America, from Oregon and central Colorado north into Alberta (El-Moursy 1970).
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