Small White Pieridae

Pieris rapae (Linnaeus, 1758)

Description: Wingspan 38-57mm. Adults have white forewings with black tips and uniform yellow underside to the hindwings. Females on average are larger than males and have more extensive dark markings. Second brood specimens of both sexes are darker than those of spring broods.

Similar Species: The Green-veined White is very similar to the Small White and in flight the two species can be difficult to separate. Compared to the Green-veined White, the Small White lacks the green coloration along the veins of the underside of the hindwing. Also the extent of black along the front margin differs in the two species. In the Small White the black apical mark extends further along the costal margin than it does in Green-veined White, but is less extensive on the side margin. The female Orange Tip is also similar but can be distinguished by the mottled patterning on the underside of the hindwing.

Key Identification Features:

Sets:  male upperside male underside female upperside female underside

Flight Period: April to October in two overlapping broods. The second brood is much larger than the first, with local numbers augmented or swamped by immigrants.

Status: This is a resident species whose numbers are annually augmented by migrants. It is recorded from all parts of N. Ireland, absent only from upland parts.

Ecology: Adults live in loose open populations. They roam the countryside looking for nectar and foodplants. They are attracted to many types of flowers, but especially pale and white flowers. Larvae feed on cultivated and wild cabbages Brassica spp, and Nasturtium Tropaeolum majus especially those growing in sheltered sites such as gardens and field margins. The green larvae are solitary resting along the midrib of the foodplant and relying on camouflage. The pupa overwinters.

World Distribution: Throughout Europe, NW Africa, Asia to Japan. Introduced into N. America and Australia.

Bradley & Fletcher number: 1550 Agassiz number: 58.007

Additional information:

UK Butterflies account


 Thompson, R. S. & Nelson, B., 2003 (Oct 2). [In] The Butterflies and Moths of Northern Ireland