D. compacta adults are brown above and orange-brown below with white or cream-coloured markings on the wings and a wingspan of approximately 23 mm (0.91 in). Males and females exhibit different markings on the wings. From above, the forewings of males each have a cream-coloured hook-shaped marking, a central spot, a band of three subapical spots, and a central band of grey sex scales, while the hindwings each have a band of four cream-coloured postmedian spots. From above, the forewings of females each have two central spots, a band of three subapical spots, a spot near the middle of the leading edge of the forewing, and a spot near the trailing edge of the forewing – lacking the hook-shaped marking and grey sex scales present on the forewings of males – while the hindwings each have a central yellow patch. From below, the forewings and hindwings of males exhibit markings similar to those above. From below, the forewings of females exhibit markings similar to those above and the hindwings exhibit a band of whitish-grey spots edged with brown, but both fore and hindwings are suffused with purplish-grey.[2][4][5]
Eggs are dome-shaped, white to cream in colour, measuring approximately 0.7 mm (0.028 in) by 0.6 mm (0.024 in), with 12–14 longitudinal ribs. As the egg develops, a purplish-red dorsal spot and lateral band appears.[2][4]
First instarlarvae are yellowish, becoming green as they feed, with a large, shiny black head and dark red prothoracic plate. Second instar larvae are similar, but develop a broad white longitudinal dorsal band with a narrow green dorsal line at the centre. Third instar larvae resemble second instar larvae, but the surface of the head is now rough and both the head and prothoracic plate have turned brown. By the fifth and final instar the larva is 18–20 mm (0.71–0.79 in) long, greenish-pink in colour, with a diffuse, pale longitudinal dorsal band, a darker central line within the dorsal band, and a narrow white longitudinal subdorsal line.[2][4]
Pupae are cylindrical, brown in colour, measuring 12–15 mm (0.47–0.59 in) long, and covered with a white powder.[2][4]
D. compacta is univoltine, with one generation each year. Eggs are usually laid singly, rarely in pairs or short rows, on the leaves of the host plant or on leaf litter. Development begins immediately, however, the larva will not emerge until autumn. Upon hatching, the larva consumes the shell of its egg before moving on. When a suitable host plant is found, the larva will construct a shelter by folding or rolling the host leaf and binding it in place with silk. The larvae are nocturnal, hiding in this shelter during the day and emerging to feed at night. Growth is slow through winter, but accelerates in spring, with the larvae beginning to pupate in late December and emerging in January and February.[2][4][5]
Adults are active between January and April and may be locally abundant in some areas. They fly low to the ground, usually in grassy areas, actively feeding on flowers. Males engage in hilltopping and can be seen patrolling their territory or perched high in the canopy.[1][4][5]
^ abcdefghGrund, Roger. "Barred Grass-skipper". South Australian Butterflies & Moths. Butterfly Conservation SA Inc. Archived from the original on 15 February 2024. Retrieved 15 February 2024.
