SeasonalityApril-August (plus one questionable January specimen) in collections, most from April-June.
IdentificationLeConte (1876) diagnosed this species as moderately large (9-11 mm), generally slender, and with a black cuticle overlain by fine, somewhat patchy, ashen-grey hairs. The background cuticle colour appears much closer to walnut-brown in our museum specimens. Separated, rounded posterior elytra tips are the key distinguishing feature for this species, it is otherwise fairly similar to Lixus rubellus Randall 1838. Within L. terminalis, the rostrum is as long as the prothorax, relatively thickened, and bears antennae near its anterior tip (1/5th of the way from the tip). The antennae have a first joint of their funicle (antennal segments between basal scape and clubbed tip) that is broader than the second joint. The prothorax is longer than it is wide, is dorsally rounded but with straight sides, and is broader than the elytra. Notches for accepting the fronts of the elytra appear almost straight in their lateral extremes, and the anterior constriction of the prothorax is gentle, giving it a rather boxy appearance. The medial angle (backwards projection along the midline of the prothorax) is small and pointed, and is situated just behind a dorsal impression which itself becomes shallower anteriorly, almost reaching the anterior edge of the prothorax. The femora of the legs are slightly club-shaped. There are punctures (pits) that are fine and dense upon the rostrum (becoming coarser on its sides). Punctures upon the prothorax are a mixture of interspersed fine and coarse pits; and are coarse, moderately deep, and widely spaced in a linear arrangement upon the elytra.