Description
Thymelicus lineola is very similar to T. sylvestris and both species fly from May till August.
T. lineola is slightly smaller than T. sylvestris.
Males have a distictive straight, black band of androconial scales running parallel to the costa on the forewing.
The underside of the antennae clubs are black. the caterpillars are green, with light yellow logitudinal lines. The head has light yellow and dark brown lines. The eggs are laid in strings, inserted into the flower sheaths. The fully developed caterpillars hatch in April.

Size
The wingspan is about 20 mm. De full grown caterpillar has a length of 25 mm.

Habitat
Prefers dry grass lands and roadside verges. Places with taller grasses flowers.

Foodplant
A diversity of grasses such as Phleum pratense (Timothy-grass), Holcus mollis (creeping soft grass), Calamagrostis epigejos (wood small-reed), Agrostis capillaris (Bent), Triticum aestivum (bread wheat).

Flight season
Fiels in 1 generation, from May till August.

Distribution
Common in Europe with exception of the high north. Accidentally introduced into Canada in 1910 in hay bales, now widely spread over north America. A study showed over 5000 lineola eggs in a single bale.