The Lepidoptera Log - by Steve Woodhall
What are all those little white butterflies ?
Every so often we are inundated with them. Let's find out more...
White butterflies stand out against most backgrounds and make themselves obvious! Some of them may occur in large swarms we call ‘migrations’ but that’s not really a helpful description. ‘Migration’ implies travelling from A to B, and a return journey, as do birds like Swallows or mammals like the Wildebeest in East Africa. With butterflies there may be an overall direction they follow but they are too short-lived to travel very far to a destination in one generation and then return as adults. Sometimes it’s merely a case of conditions favouring a mass emergence of adults in a particular area.
All those little white dots fluttering across the landscape can appear confusingly similar to one another from a distance. If we look closer, we might see subtle differences in size, colouring or markings. When we look at them more closely it can become obvious that we aren’t looking at a generic ‘white butterfly’.
In Europe white butterflies are sometimes viewed as pests. This is because the caterpillars of some species, like the Large White, Pieris brassicae, are capable of damaging valuable crops like brassicas, or cabbages. In English this gave them the name ‘Cabbage White’. Because many farmers in South Africa originated in Europe this name stuck to all our white butterflies even if their caterpillars never touch cabbage!
Some of Africa’s white butterflies are common and widespread and there are several species like that. Others are less common but get mixed in with the rest. With a few exceptions in other families, the white butterflies we see in Africa are in the same family seen around the world – the Pieridae.
Here we’ll show you some examples to help you recognise the ones you’ll see most often.
Pioneer Caper White ♂
Belenois aurota
Pioneer Caper White ♀
Belenois aurota
African Caper White ♂
Belenois creona severina
African Caper White ♀
Belenois creona severina
Forest Caper White ♂
Belenois zochalia zochalia
Forest Caper White ♀
Belenois zochalia zochalia
Let’s start with the Caper Whites, genus Belenois. These are smallish butterflies with wingspans of 40-50mm. Pioneer Caper White is the well-known one that often swarms just before Christmas and usually flies in an easterly direction. In Southern Africa they appear to originate in the Kgalagadi region, but they’re found across the drier areas of Africa to Kenya, Tanzania and Nigeria. They are also found in Madagascar and as far east as western India and Sri Lanka. The female in particular has more brown colouring that explains its alternative common name of ‘Brown-veined White’.
African Caper White is less likely to be found in arid country; in South Africa it’s found in the moister savanna and forests in Limpopo, Mpumalanga, eSwatini, KwaZulu-Natal and the Eastern Cape. It can also swarm in large numbers and appears to get ‘caught up’ in Pioneer Caper White swarms.
Females of both species tend to have more extensive dark borders than males, and more yellow colouration.
Males of African Caper White are often mistaken for Pioneers because their upper sides are quite similar. Try to have a look at the underside hindwing because its markings are different with a lot more yellow. Female African Caper Whites have very wide dark borders and are difficult to mistake for any other ‘white’ butterfly – their upper sides are more often cream or even yellow.
One Belenois species that tends not to swarm is the Forest Caper White, Belenois zochalia zochalia. It’s found in moist Afromontane forests along the eastern escarpment, as well as in forest remnants in the Magaliesberg and Witwatersrand in Gauteng. They are quite variable in appearance. Not all females have the lovely yellow hindwings, and the inland examples have less well-marked undersides.
Their caterpillars feed on plants in the Caper family, Capparaceae. They use mostly Boscia, Capparis, and Maerua species.
This genus of butterflies is in the Pierinae subfamily of the family Pierinae.
Pointed Caper White ♂
Pseudanaphaeis gidica abyssinica
Pointed Caper White ♀
Pseudanaphaeis gidica abyssinica
Closely related to the genus Belenois – until recently it was in that genus – is the genus Pseudanaphaeis, which only contains one species, the Pointed Caper White. They are easily mistaken for Pioneer Caper Whites but they are distinguished by their pointed forewing tips and the underside hindwings that have a postdiscal extra row of dark marks and have a ‘streaky’ appearance.
Unlike the Pioneer Caper White there is a yellow form of the female, form doubledayi.
This species is found in frost-free savanna all over tropical and subtropical Africa. They may take part in multi-species migrations.
African Migrant ♂
Catopsilia florella
African Migrant ♂♂ on wet cement
Catopsilia florella
African Migrant ♀ yellow form
Catopsilia florella ♀ form florella
African Migrant ♀ white form
Catopsilia florella ♀ form hyblaea
The other well-known ‘migrant’ is the African Migrant, Catopsilia florella. It’s a larger butterfly than the Caper Whites, with a wingspan between 55 and 65mm, females being larger. It’s the only local white butterfly in the Pierid subfamily Coliadinae.
Their name is appropriate – they definitely do migrate. Sometimes they fly en masse in an easterly direction, but often they are simply ‘everywhere’! The caterpillars feed on plants in the Fabaceae (bean and pea) family, especially in the genera Senna and Cassia. The so-called ‘Peanut Butter Cassia’, Senna didymobotrya, is probably the most popular host plant. It’s a very widespread invasive weed, which probably explains the extreme abundance of the adults after good rains.
Like many other ‘whites’ the males are often found sucking salt-laden moisture from wet mud. They need the salts to develop their male gametes (sperm) and improve their chances of successful mating. Wet cement, as seen here, can be very attractive to them. Males are usually greenish white with a pale-yellow underside when fresh, which fades to greenish white. As they age the pigments change chemically, and really old males can be sky-blue.
Females are variable in colour with two main forms: bright yellow (form florella) and creamy-white (form hyblaea). Intermediates are sometimes seen. The yellow forms tend to be more numerous in winter when many plants’ leaves turn yellow. They are sometimes seen seeking out such leaves and hiding amongst them to shelter from the cold.
African Ant-heap White ♂
Dixeia charina charina
African Ant-heap White ♂
Dixeia charina charina ♂ form anactoriae
African Ant-heap White ♀
Dixeia charina charina
African Ant-heap White ♀
Dixeia charina charina
Most of our white butterflies are in the subfamily Pierinae. The genus Dixeia (Ant-heap Whites) bear certain similarities to the Caper Whites in the genus Belenois. They are in the same subtribe, Aporiina. They tend not to swarm in large numbers but after good rains there may be plenty on the wing.
African Ant-heap White, Dixeia charina charina, is slightly smaller than the Belenois species with a wingspan of 34-42mm. The males are very plain above and not easy to tell apart from the other common Dixeia in our area, Small Ant-heap White, Dixeia pigea. Unless you can see the underside, that is. African Ant-heap White male undersides always have black speckles on a white ground. The weight and pattern vary according to the season and habitat. The example on the right is about the average.
Females are more heavily marked with a dark spot on the forewing as shown. They are generally a warmer, creamier white. Like the males the degree of dark speckling on the underside hindwing varies.
This butterfly abounds on the southeastern side of South Africa and is often found in the arid thickets of the Eastern Cape. Further north it occurs in East Africa as far north as Ethiopia and on Madagascar.
Ant-heap Whites get their common name from the tendency of some species to congregate around anthills (termite mounds). One of the host plants is Cadaba termitaria, known as the Grey-leaved Worm Bush, but most of them feed on the related Capparis species (Caper-bushes) or Maerua (Bush-cherries). These also tend to grow on termite mounds; the well-drained, nutrient-rich soil helps them to grow quickly and develop lush foliage.
Small Ant-heap White ♂
Dixeia pigea
Small Ant-heap White ♂
Dixeia pigea
Small Ant-heap White ♀
Dixeia pigea form pigea
Small Ant-heap White ♀
Dixeia pigea form alba
Small Ant-heap White ♀
Dixeia pigea form rubrobasalis
Small Ant-heap White ♀
Dixeia pigea form luteola
Small Ant-heap White ♀
Dixeia pigea form lutea
Small Ant-heap White ♀
Dixeia pigea form lutea
Small Ant-heap White, Dixeia pigea is on average slightly larger (wingspan 40-52mm) than African Ant-heap White, which makes its common name a bit strange! The males are very similar above, but Small Ant-heap White males lack the speckling on the underside – there is usually a series of submarginal black spots as shown on these mud-puddling individuals. The other way to tell them apart is that Small Ant-heap White has an ochre-coloured edge to the costa of the underside hindwing, which African Ant-heap White lacks.
The females are enormously variable in both colour and extent of dark markings. In general, dry season forms have less extensive dark marks, and wet season forms, more. Form pigea is the ‘typical’ form. Form alba is a dry season form with reduced marginal black. Form rubrobasalis has reddish-orange wing bases rather like a Dotted Border (see below). Form luteola is a rare totally-orange form from the northern part of the butterfly’s range in South Africa. Form lutea is a very attractive deep yellow form from KwaZulu-Natal and Mpumalanga.
This butterfly is on the wing all year round, being commoner in the summer months. It is found across a vast area of Africa, in heavy savanna and moist woodland, as far north as Ethiopia and west to Cameroon, as well as Madagascar. Under optimal conditions it may swarm in large numbers.
Eastern Diverse Albatross
Appias epaphia contracta ♂
Eastern Diverse Albatross
Appias epaphia contracta ♀
East African Albatross
Appias sabina phoebe ♂
East African Albatross
Appias sabina phoebe ♀
Genus Appias are another type of ‘little white butterfly’ from a different subtribe, the Appiadina. This is more widespread in Asia where they have the name ‘Gulls’ as well as Albatrosses. The two local species, Eastern Diverse Albatross Appias epaphia contracta and East African Albatross Appias sabina phoebe are very similar in the males with wingspans in the 40-55mm range, and their upper sides are white with streaky black marks at the forewing tip and outer margin. Eastern Diverse Albatross is common along the eastern side of South Africa in forest and heavy woodland and extends across most or Africa. East African Albatross is also widely distributed in Africa, but in South Africa is confined to the eastern areas of Limpopo, KwaZulu-Natal, the Eastern Cape and eSwatini. Until recently it was a very rare sighting locally, but it has spread southwards in recent years.
The way to tell the males apart is to examine the underside of the base of the forewings. East African Albatross is plain white there. Eastern Diverse Albatross has a similar yellow flush to the hindwing.
The females are quite easy; Eastern Diverse Albatross is a black and white butterfly with the black borders being wide in wet season specimens and narrower in the dry season. East African Albatross females have similar wing margins to the males but have an orange wing base like a Dotted Border; some individuals have all-yellow hindwings. This species is seldom seen in South Africa – you have to go to the forests to see it.
These species do not ‘migrate’ or swarm, but they may become caught up with other species that are swarming. The two species have different host plants. Eastern Diverse Albatross uses a wide range of plants in the Capparaceae – Boscia, Cadaba, Capparis, and Maerua, as well as Cleome (Cleomaceae) and Salvadora (Salvadoraceae). In South Africa, East African Albatross is only known to use Drypetes gerrardii (Putranjivaceae)
Eastern Dotted Border
Mylothris agathina agathina ♂
Eastern Dotted Border
Mylothris agathina agathina ♀
Twin Dotted Border
Mylothris rüppellii haemus ♂
Twin Dotted Border
Mylothris rüppellii haemus ♀
Another member of subtribe Aporiina is the genus Mylothris. This is different to the other genera in the subtribe; its larval host plants are in the family Santalaceae (Loranthaceae), and the adults contain toxins metabolised from the host plants by the larvae.
The adults do not migrate or swarm but may be found in large numbers where their host plants grow in abundance. There are three species in South Africa, two being common – Twin Dotted Border Mylothris rüppellii haemus and Eastern Dotted Border Mylothris agathina agathina (which is the more widespread). A third, Sulphur Dotted Border, Mylothris trimenia, is rare and confined to cool Afromontane forests in the east.
Female Twin Dotted Border is seen here ovipositing on the hemiparasitic Hairy Mistletoe Erianthemum dregei. The other two species use the same plant, but Eastern Dotted Border uses, in addition, Cape Sumach Osyris compressa and African sandalwood Osyris lanceolata, which widens its range to cover Cape Town.
Like many distasteful butterfly species, Dotted Borders tend to have a slow, leisurely flight pattern. Other species of Pierid may mimic Dotted Borders, like the females of the Small Ant-heap White form rubrobasalis and the East African Albatross (among others). This is almost certainly a form of mimicry as seen in butterflies like the female Common Diadem, Hypolimnas misippus.
African Meadow White
Pontia helice ♂
African Meadow White
Pontia helice ♀
Finally, we come to subtribe Pierina, which has the classic Brassica-feeding ‘whites’ typical of the northern hemisphere. The only native member of this group is the African Meadow White, Pontia helice. It’s a dainty, small butterfly with a wingspan of 35-43mm. It’s often the first butterfly to emerge in spring, sometimes as early as August. Males are pure white on the upper side with a black wingtip containing white spots; there is a square spot at the end of the forewing cell, and the hindwings are white with dark marginal marks and tracery along the veins. The female has a dark spot at the inner margin of the forewing, and a grey postdiscal band on the hindwing containing a row of white marginal spots.
African Meadow White is often mistaken for the Pioneer Caper White because it has superficially similar markings. On the upper side a close inspection will show that the forewing tips are smaller than those of the African Meadow White and contain fewer white spots. The mark at the end of the cell is not as square in Pioneer Caper White as it is in African Meadow White and it’s often teardrop shaped or joins with a dark costal band. The undersides can look similar as well but the dark lines along the hindwing veins are black or brown in Pioneer Caper White whereas in African Meadow White they are made up of a micro-mosaic of yellow and black scales.
African Meadow White larvae do not feed on Capparaceae; they only use Brassicaceae like Rocket Eruca sativa, Sweet Alyssum Lobularia maritima, Indian Mustard Brassica juncea or Peppercresses Lepidium species. They haven’t been recorded feeding on cabbages Brassica oleracea so it’s a bit of an insult when people call them ‘Cabbage Whites’!
Large (Cabbage) White
Pieris brassicae ♂
Large (Cabbage) White
Pieris brassicae ♂
The famous ‘Cabbage White’ (also Pierina) actually DOES fly in South Africa. It’s not 100% certain that ‘Cabbage White’ refers to this species or the even more destructive (to crops) Small White Pieris rapae, which does not occur here despite many people using Google and getting it wrong. So far it hasn’t developed a reputation for being a pest of Brassica crops here. It appeared in the Western Cape in 1994 and has spread along the coastal hinterland as far west as Oudtshoorn and as far north as Swakopmund in Namibia. So far, it appears to prefer the exotic garden subject Nasturtium (Tropaeolum sp.) as its host plant, and is common on the Cape Peninsula.