Saturday, 28 November 2009

Butterflies of Bristol 6: The Egg Fly butterflies

The egg fly butterflies of the genus Hypolimnas are a diverse group of nympalids with a worldwide distribution. We have at various times four species at Bristol, of which the two you are most likely to see are the Variable Eggfly H.anthedon, and the Red-Spot Diadem, H.usambara. You may also see the Great eggfly H.bolina and the Mimic Eggfly H.misippus.

Saturday, 21 November 2009

Butterflies of Bristol 5: The Charaxes

Moving on from South American butterflies to those from Africa, one of the more obvious nymphalids on show are the various species of Charaxes. This is a huge group of species, with a collective range extending across the Old World tropics. A single species, C.jasius, breeds around the Mediterranean, and I have seen these on several occasions. The best time is probably late summer, and the best location is a fig grove – the Charaxes butterflies are feeders on fruit and dung rather than flowers. Charaxes butterflies often have intricately marked or cryptic undersides to their wings. Upper sides may be marked in shades of orange or brown for the most part. At the zoo we usually have three species:

Monday, 16 November 2009

Butterflies of Bristol 4: The Morphos

The most spectacular and instantly recognizable butterflies we have at Bristol are the Common Morpho butterflies, Morpho peleides. Like the owl butterflies, to which they are fairly closely related, they belong to the Satyrinae, the same nymphalid subfamily that includes the familiar brown butterflies of Europe. Currently the Morpho tribe is divided into three genera:

Antirrhea – 11 species
Caerois – 2 species (leaf mimics)
Morpho – 29 species in several subgenera

Sunday, 8 November 2009

Butterflies of Bristol 3: The Glasswings

At this time of year the most prominent butterflies to be seen in the butterfly house are the clearwing butterflies. These butterflies (we have the Frosted Glasswing Greta oto) belong to the Ithomiini, a subdivision of the milkweed butterflies Danainae, which in turn belongs to the gigantic family Nymphalidae. Butterflies of this group are often distasteful to predators as they sequester toxic alkaloids from the larval foodplants, which mainly in the case of the Ithomiines are members of the nightshade family Solanaceae. Some however do not depend on the larvae as a source of toxins; instead the adults obtain alkaloids from flowers or rotting leaves. This is especially the case with the males, which also use the toxins as pheromones in their courtship of females.

Tuesday, 3 November 2009

Butterflies of Bristol 2: The Heliconiines

One of the most obvious groups of butterflies to be seen in butterfly houses around the world are the various species of the Nymphalid tribe Heliconiini. This is an almost entirely Central and South American group of 69 species and innumerable local colour forms, characterised by a strong preference for members of the Passifloraceae as larval food plants. Passiflora contains some potent toxins, which are taken up by the larvae and render the adults distasteful to predators, especially birds. As a result, they tend to be confident and vigorous flyers, usually with warning colours of red, black and yellow in a variety of patterns, which makes them very obvious when in a butterfly house.