Ruán beag in Gaeilge. The Small Tortoiseshell is the most familiar garden butterfly across Ireland, recorded in every county and flying from March emergence through October in warm years.
Identifying the Small Tortoiseshell in the field
Orange upperside with black-and-cream forewing bars, blue-and-black marginal band on both wings. Underside is dark, marbled brown, and gives the closed-wing individual a bark-like camouflage on tree trunks and fence posts. Wingspan 45 to 55 mm.
Confusion species
The Painted Lady (Vanessa cardui) shares the orange base colour but is larger, paler-buff on the forewing, and lacks the blue marginal spots. See the confusion page for a side-by-side comparison.
Life cycle and foodplant
Two broods in Ireland in warm years. Females lay egg batches on the underside of Common Nettle (Urtica dioica) leaves in sunny, sheltered positions. Larvae feed communally in a silk web before dispersing to pupate. Adults overwinter in sheds and outbuildings and re-emerge on the first warm March days.
Recorded in 22 of 26 Irish counties in the National Biodiversity Data Centre atlas, with the strongest concentrations in Munster and eastern Leinster. Numbers dropped through the 2010s and partially recovered from 2019 onward.1
Source: National Biodiversity Data Centre butterfly atlas 2014 to 2019, and Butterfly Conservation Ireland annual review 2024.
Conservation status
Least Concern in the Butterfly Conservation Ireland Red List (2010, revised 2019). Numbers dropped through the 2010s across the British Isles for reasons not yet fully understood, and have partially recovered from 2019 onward. Recording effort remains important for tracking the trend.
Every sighting counts
Butterfly Conservation Ireland and the National Biodiversity Data Centre track changes in Irish butterfly populations through recorder submissions. Add a sighting, and a named contributor will verify it within seven days.
