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The plain wing margins of this small (25-35 mm wingspan) brown skipper help to separate it from other skippers in Alberta. The dorsal wing surface appears brown or orange-brown and has no distinct markings (Acorn, 1993). In this aspect it is similar to the Dun Skipper (Euphyes vestris); however, Oslar's Roadside Skipper is smaller and has a smaller black stigma on the dorsal forewing than the Dun Skipper. The ventral side of the hindwing of Oslar's Roadside Skipper is covered in grey scaling and there is a pale-grey postmedian band; both are lacking in the Dun Skipper. Another similar species is the Roadside Skipper (Amblyscirtes vialis). However, it has white wing markings on the outer edges of the ventral fore and hindwings (Guppy & Shepard, 2001) and has a purple sheen on the ventral hindwing surface (Acorn, 1993); both are lacking in Oslar's Roadside Skipper. Eggs are white (Bird et al. 1995). First instar larvae have a cream coloured head and black collar, their body is creamy yellow; as they feed on grass they become greenish yellow with a dorsal line (Layberry et al. 1998; Opler & Wright 1999). Pupae are not described.

First instar or mature larvae overwinter and pupate in the spring when they have finished eating (Bird et al., 1995). After adults emerge, males are territorial, perching on sandy spots in gullies and ditches to wait for receptive females (Acorn, 1993; Opler et al., 1995). Females lay eggs on the underside of grass leaves (Bird et al., 1995).

Unknown for Alberta. Larvae are suspected to feed on Blue Grama (Bouteloua gracilis) or other grasses (Bird et al., 1995). In Colorado, host plants include Side-oats Grama (Bouteloua curtipendula) and other grasses (Bird et al., 1995; Opler et al., 1995). Adults feed on flower nectar (Opler et al., 1995).