The Painted Ladies of Our World

One might speculate about the reasons for the Thistle butterfly's enormous distribution. The most important reason here is probably the species' migratory behaviour. Since it constantly migrates over large areas, the possibility for relict populations to form new species is prevented, as these are continually intermixed with migrating animals. These migrating animals have also reached nearly all places on our earth. Moreover, the species feeds on all manner of herbs, with us mainly thistles, hence the name. This greatly facilitates the possibilities of finding food wherever it chooses to travel and reproduce.

On the American continent there are at least 8 species, of which 6 are in South America. Our Thistle butterfly, Cynthia cardui, is found as far down as northernmost Colombia. However, it is far from as dominant on the American continent as in Europe and Asia. As to the reasons for this, one perhaps cannot speak with certainty. Nevertheless, one can make certain speculations, and I would like to hear the views of Insectifera's readers on this.

In the Old World, the Mediterranean does not constitute an obstacle for the Thistle butterfly. On the contrary, the large warm winter area around the Mediterranean with coastal regions north of the Sahara and areas towards India provide perfect places from which to constantly migrate. It has been speculated that recent years' invasion came from the regions around the Caucasus.

Central America is an enormously much smaller area than Africa and southern Asia. Perhaps this hinders the species' opportunities to dominate over species within the same genus there and thus gives these the opportunity to flourish. Looking at the distribution area, it seems as if the species is programmed to migrate northward. It is admittedly found in South Africa but is quite rare there. In South America and Australia it is absent, as described above. In general terms it can also be noted that very few species have colonized South America and Australia from the north. Probably only a small percentage of these continents' number of species has colonized the continent from the north. This applies especially to South America, which has been isolated from the rest of the world for a very long time and now has contact only via the narrow Panamanian isthmus.

Remarkable, however, is that South America harbours so many other Thistle butterfly species. Did the origin of these species lie there already when the continent separated from Africa when Gondwanaland split 80 million years ago?

I myself have seen in 30 million year old limestone layers in England a butterfly that was very similar to our own Thistle butterfly. It was so well preserved that even the colours could be discerned! What surprised me most was how similar it was to our own species today. One then asks oneself whether, if it looked like today's animal already 30 million years ago, it should not then 30 million years ago also have been able to look as it did a further 30 million years before. We are then almost back to the time of Gondwanaland's dissolution. When one like me has studied Africa's and South America's butterfly fauna in parallel for 20 years, one cannot sufficiently marvel at the similarities between many of these continents' species. Presumably it is all much older than was previously thought.

South America harbours, in addition to our own C. cardui, the following Thistle butterfly species:

The image material is taken from Bernard D'Abrera's extraordinary book work on our earth's butterflies. The animals in question are from "Butterflies of the Neotropical Region, part 4".

Vanessa braziliensis

Vanessa altissima
Andes: Ecuador, Peru, Bolivia

Vanessa myrinna
Venezuela–Bolivia, Brazil

Vanessa terpsichore
Chile–?, Colombia–?

Vanessa carye
Andes: Colombia–Chile

In North America, in addition to our own Thistle butterfly, also flies:

Vanessa anabella
Canada–Guatemala

Vanessa virginiensis
North America, Caribbean

Of some interest in this context can also be that two of the above species, virginiensis and carye, have also been found on the Galapagos Islands 100 miles out in the Pacific Ocean! These fine drawings are taken from the book on the Galapagos Islands' animal world!

Cynthia virginiensis Cynthia carye

Regarding these Thistle butterflies one can easily establish that the same colour variation occurs in most species hatched during different seasons as in our Thistle butterfly Cynthia cardui. Similar to with us, animals hatched during summer are usually somewhat redder than spring animals, which are more yellow.

As appears above, the Thistle butterfly's relatives are all bound to the New World. The Thistle butterfly's close relative the Admiral, Vanessa atalanta, has a similar but somewhat smaller distribution area than the Thistle butterfly. A major difference is, however, that none of the other "Admirals" are found in America. They are all found in Asia and Australia.

The Admiral occurs with several species with our own admiral as the completely dominant one with a distribution area that is circumpolar, which means that it is found in North America, North Africa and northern Asia. It does not, however, go as far south as the Thistle butterfly in Africa and Asia and is completely absent in South America, Tropical Africa, Australia and the southernmost Asia.

The species does, however, have several close and very interesting relatives. The best known is probably the Indian Admiral, which has its main distribution from India via China to Japan. On Ceylon and on the southern tip of the Indian peninsula flies the subspecies Vanessa indica nubicola. The Indian Admiral is, however, also found on the Canary Islands and Madeira and now also on the south coast of the Iberian Peninsula. It differs markedly in colour from the Indian animals, as the Canary Island ones are much redder.

This species' distribution area is something of a mystery with two occurrences so far apart. The explanation could be that the area between the Canary Islands and India consists mostly of desert. The Admiral, both Linnaeus' as well as the Indian, does not seem to like this type of landscape as well as the Thistle butterfly. The Sahara desert has evidently expanded during the Quaternary period and may then have cut off the Canary Island animals. The common Admiral or Linnaeus' Admiral as I prefer to call it, flies together with the Canary Island one on the Canary Islands and Madeira.

Bernard D'Abrera, who has published the great work on our earth's butterflies, has also been the first to note a remarkable difference between the Indian and the common Admiral. The Indian Admiral has much longer antennae than our Admiral!

The explanation for the remarkable distribution could of course also be that the species once migrated and then ended up on the Canary Islands where it subsequently managed to persist. I am, however, sceptical of this explanation as Vanessa indica does not have the common admiral's migratory behaviour.

Vanessa atalanta
North America, Europe, North Africa, northern Asia

Vanessa indica vulcania
Canary Islands, Madeira (Spain, Portugal)

Vanessa nubicola

Vanessa indica
Southernmost India, Ceylon

India, China, Japan

In Southeast Asia, in addition to the Indian Admiral and the Ceylonese Admiral, there is also an interesting relic on the remarkable island Sulawesi. Actually, it is not surprising that precisely this island harbours the only relative of our Admiral outside its enormous distribution area in the Old World. Sulawesi or Celebes as the island is sometimes called harbours many very remarkable butterflies, of which a large number are endemic. The island also seems to have been cut off from the rest of the Southeast Asian archipelago for long periods, as many species found both west and east of Sulawesi are absent on this remarkably shaped island. Actually it is only the highest parts of the island's mighty mountain chain that today reach above the water surface.

On Sulawesi's southernmost part flies rarely the remarkable Vanessa buana. Not much seems to be known about this butterfly.

In the mountains of western Sumatra flies Vanessa samani, which is quite similar to our own admiral but somewhat smaller and lighter.

Vanessa buana
Southernmost Sulawesi

Vanessa samani
Western Sumatra

The Admiral's distribution area with its very closely related species and subspecies can perhaps be interpreted as showing that it is in decline or that it once had a larger distribution area than today. This can perhaps be explained by the fact that it in Asia today, that is during the last few million years, no longer has the same migratory drive as with us. This makes it easier for local populations to develop into "good species" when genetic material is not constantly "replenished" from the parent species.

On Java, the Sunda Islands and on Mindanao, the southernmost of the large Philippine Islands, flies the smallest and perhaps least conspicuous of the earth's Admirals, Vanessa dejeanii.

In southern Australia and on New Zealand flies Vanessa itea, which is called the Yellow Admiral. It differs markedly from the other admirals on our earth with its large yellow patch on the forewing.

Vanessa dejeanii Vanessa itea

On New Zealand also flies perhaps the most beautiful of all the earth's Admirals, the dark blue, red-spotted Vanessa gonerilla.

Perhaps the most remarkable Vanessa species is the Hawaiian Admiral. It is somewhat of a transitional form between the Thistle butterfly and the Admiral. With its isolated location one can only speculate about its origin. It is still found today on most of the large islands in the group but is not common anywhere.

Vanessa gonerilla Vanessa tameamea

References

Bernard D'Abrera, Butterflies of the Neotropical Region
Butterflies of Australia
Butterflies of the Oriental Region
Butterflies of the Holarctic Region

Charles Mc Cubbin, Australian Butterflies

W.B.R. Laidlaw, Butterflies of New Zealand

Norman Hickin, Animal life of the Galapagos

James A Scott, 1986, The Butterflies of North America

William H Howe, 1975, The Butterflies of North America

A.M. Emmet, The scientific names of the British Lepidoptera

Etsuzo Tsukada, Butterflies of the South East Asian Islands

Gästrikland's Entomological Association has awarded

Hans Lundberg, Stockholm

1996's GOLDWING PRIZE

The Goldwing Prize is the association's environmental award for commendable efforts for the environment with particular emphasis on the preservation of biological diversity.

The motivation for this year's prize reads:

"For a selfless and sincere commitment in the important work of preserving Borneo's rainforests"

The prize was awarded on: 23 January at 19.00 at the Forest Museum Silvanum, in Gävle

The actual prize ceremony was a joint arrangement with the Study Advancement Association in Gävle.

Hans Lundberg, left, receives 1996's Goldwing Prize from the chairman of Gästrikland's Entomological Association, Göran Sjöberg