Dixeia pigea

Dixeia pigea, the ant-heap small white[1] or ant-heap white,[2] is a butterfly in the family Pieridae that is native to Africa.

Two females of different forms viewed from the side

Ant-heap white
Male
Female
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Lepidoptera
Family:	Pieridae
Genus:	Dixeia
Species:	D. pigea
Binomial name
Dixeia pigea (Boisduval, 1836)
Synonyms
Pieris pigea Boisduval, 1836 Pinacopteryx alba Wallengren, 1857 Belenois inana Butler, 1870 Pieris pigea ab. rubrobasalis Lanz, 1896 Pieris pigea ab. caffraria Lanz, 1896 Pieris rubrobasalis var. nitida Aurivillius, 1899 Pieris saalmuelleri Aurivillius, 1899 Pinacopteryx astarte Butler, 1900 Dixeia astarte Pieris kueckeni Suffert, 1904 Pieris wagneri Suffert, 1904 Pieris rubrobasalis ab. lathyana Strand, 1909 Pieris elia Strand, 1912 Pieris pigea f. lathyi Hulstaert, 1924 Pieris leplaei Hulstaert, 1924 Pieris leplaei f. reducta Hulstaert, 1924 Pieris pigea pigea f. vulgaris Ungemach, 1932 Pieris pigea pigea f. rubritincta Ungemach, 1932 Pieris pigea pigea f. lutea Ungemach, 1932 Pieris pigea ab. citrina Romieux, 1934 Dixeia pigea f. citreus Talbot, 1943 Dixeia pigea f. luteola Talbot, 1943 Dixeia pigea f. lutescens Talbot, 1943 Dixeia pigea f. erubescens Talbot, 1943

Description

The wingspan is 40–48 mm for males and 40–52 mm for females.[3] The upperside of the wings of males is pure white with a narrow black forewing tip and small black dots on the hindwing margin.[1] The underside is whitish with two rows of black spots on the hindwings,[1] with the inner row sometimes absent or incomplete. The female has several colour forms,[1] but is usually pale yellowish white on the uppersurface with heavier black markings than the male,[1] and has a dark spot on each forewing. There is a rare female form (luteola[3]) where the upperside is orange yellow[1] or deep apricot.[3] The underside of females is similar to the male but the rows of black dots are more pronounced and the base colour is pale to bright yellow. Another rare form (rubrobasalis) has orange suffusion at the base of the underside of the forewing[1] and a creamy-yellow upperside.[3] The dry-season form (alba[3]) has reduced black markings.[1] A distinguishing feature of D. pigea is that the hindwing costal has a yellow streak, unlike other Dixeia species.[3]

• 
  Female form rubrobasalis from Limpopo Province, South Africa
• 
  Male viewed from the side; showing the yellow streak on the hindwing

Distribution

This species is found from the Eastern Cape province of South Africa through KwaZulu-Natal, Swaziland, Mpumalanga and Limpopo Province,[4] to Mozambique, Zimbabwe, Ethiopia, DRC, Angola and Cameroon.[2]

Life cycle

Pupa of Dixeia pigea

Eggs

Groups of tiny, elongated eggs are laid on the undersurface of the leaves of the food plants.

Larvae

The larvae are green; pale green on the back and darker green on the sides when young, and develop two rows of pale green blotches down the length of the body as they grow older. The food plants are Capparis sepiaria and Capparis tomentosa.[1]

Pupae

The pupae have an unusual shape, with a pointed 'nose' and a notable spike on each side of the body protruding from a broad, flattened area midway down the body. There is a smaller spike both to the fore and rear of each of these larger spikes, and a small spike on each side of the body just to the rear of the head. The larger spikes resemble to some extent the double, hooked thorns on the stems of the food plant, Capparis tomentosa (see image). The pupae may be pale green, dark green or brown in colour. The wing areas show whitish or yellowish with dark spots near to hatching and the body becomes greyish.

Adults

The flight period is all year.[1] They have been described as having a medium-fast, random flight pattern[1] or as a rather weak, slow flying butterfly.[5] They keep to open areas[1] in riverine forest and thick bush[5] or the edges of bush areas.[1] Both sexes feed from flowers[1] and are greatly attracted to flowering bushes exposed to the sun.[5]

Gallery

• 
  Larvae of Dixeia pigea, just a few days old
• 
  Older larvae
• 
  Larvae; the one on the left is near to pupating
• 
  Larva about to pupate
• 
  Brown pupa
• 
  Green pupa
• 
  Underside of female pupa; yellow wings showing through
• 
  Pupa near to hatching
• 
  Female hatching from pupa
• 
  Female extending wings after hatching
• 
  Side view of female
• 
  Captive raised female released onto larval food plant

References

1. Williams, M. (1994). Butterflies of Southern Africa; A Field Guide. Southern Book Publishers. ISBN 1-86812-516-5.
2. Markku Savela's pages: Dixeia, retrieved 4 August 2010.
3. Woodhall, Steve (2005). Field Guide to Butterflies of South Africa. Cape Town, South Africa: Struik. ISBN 978-1-86872-724-7.
4. Biodiversity data provided by: Data contributors to the Southern African Butterfly Conservation Assessment (SABCA) (list of contributors accessible here: http://sabca.adu.org.za/thanks.php Archived 2011-01-19 at the Wayback Machine), a joint project of the South African National Biodiversity Institute, the Animal Demography Unit, University of Cape Town, and the Lepidopterists' Society of Africa (accessed via SABCA's online virtual museum, "Archived copy". Archived from the original on 2011-01-18. Retrieved 2011-01-03.CS1 maint: archived copy as title (link), 04-08-2010).
5. Cooper, R. (1973). Butterflies of Rhodesia.

• Seitz, A. Die Gross-Schmetterlinge der Erde 13: Die Afrikanischen Tagfalter. Plate XIII 14