Banana butterfly
| Banana butterfly | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Caligo | ||||||||||||
| Huebner , 1819 |
The butterflies of the genus Caligo from the family of noble butterflies (Nymphalidae) are called banana butterflies . The genus includes 21 species, which are among the largest of the Neotropics . The caterpillars feed on bananas , arrowroots and heliconias .
features
The moths are large and have a beige to brown basic color. The fore wing length ranges from 65 to over 90 millimeters in Caligio eurolochus sulanus . The wings of the males shimmer partly dark blue. The undersides of the wings have a contrasting brown, black and cream-colored pattern. On the hind wing there is a large dark eye spot , which is outlined in a thin beige and black color. Smaller eye-spots are partly on the hind and fore wings. Due to their attention to detail, the large eye spots of the Caligo species (cf. Latin caligo oculorum : darkening in front of the eyes , star ) are among the best imitations of eyes in animals. The dark core with a light half ring on it and the light edge strongly resemble a light iris with a dark pupil that has a reflection. They can be interpreted as an owl's eye which is surrounded by a simulated plumage structure, which is why the Caligo species also have the common English name Owl butterflies . However, it is controversial whether these eyespots imitate the eyes of a certain animal or whether they serve as secondary protection when a predator comes too close. The animals are primarily protected by their high-contrast pattern on the underside of their wings, a bark mimetic , when they rest on tree trunks with closed wings during the day.
The caterpillars have the typical features of the Brassolini tribe , a head capsule with several, partly branched, thorns and a conspicuously forked tail. There are several short triangular spines on the back, which distinguishes them from the similar caterpillars of the genus Opsiphanes . In the first stages the caterpillars are green, later they turn brown. At the last stage, they can weigh 16 grams.
Way of life
Caterpillars
Apart from bananas (Musacaceae), which first came to America with the Europeans, the caterpillars prefer to feed on heliconias (Heliconiaceae) and arrowroot plants (Marantaceae). Palm plants (Arecaceae) and disc flower plants (Cyclanthaceae) are rarely used as food plants. The caterpillars are nocturnal and spend the day in sleeping colonies on the forage plant. The young green caterpillars are well adapted to the leaves of the forage plants, on which they form sleeping colonies on the midribs during the day. Older caterpillars are brown like banana trunks or the false trunks of heliconias and their sleeping colonies on them are difficult to recognize. At this stage they are already too big and noticeable to stay on the leaves. Caterpillars of different stages feed together side by side without causing cannibalism.
The caterpillars grow more slowly on original food plants such as heliconias, the causes are not precisely known. It is believed that lower nitrogen intake slows growth. The assumption that the tannins contained in the plants are responsible for the stunted growth has been refuted, since their concentration is much lower than originally assumed according to recent studies.
butterfly
The moths are crepuscular and sit on tree trunks during the day. They drink the juice from rotten or fermenting fruits and can live up to seven weeks ( Caligo memnon ).
Enemies
Since the caterpillars are not known to be inedible or toxic, good camouflage is the only known way for the caterpillars to protect themselves from predators. It has been observed that they are not attacked by ants, a possible chemical defense is not yet known.
An egg parasitoid from the Trichogrammatidae family (superfamily wasps ) is one of the main enemies of the moths. These tiny wasps cling to the hind wings of both sexes. When the females lay eggs, the wasps leave the moths and parasitize the eggs. Up to 30 wasps can develop from one egg.
In banana plantations, some Caligo species can become pests, especially after the use of insecticides, as these also kill the parasitoids that attack the caterpillars and prevent unchecked reproduction.
distribution
The genus is distributed from Mexico to South America , most of the species are found in the Amazon basin . The moths live in the lowlands and usually do not rise above 1000 meters. The vertical distribution ends at 1600 meters.
Systematics
At present, 21 species are assigned to the genera, in some cases subspecies are still differentiated. Some species cross in the wild and in butterfly farms, so the species status is not guaranteed for all species.
- Caligo arisbe
- Caligo atreus
- Caligo bellerophon
- Caligo beltrao
- Caligo brasiliensis
- Caligo euphorbus
- Caligo eurilochus
- Caligo idomeneus
- Caligo illioneus
- Caligo martia
- Caligo oberthurii
- Caligo edipus
- Caligo oileus
- Caligo placidianus
- Caligo Prometheus
- Caligo superbus
- Caligo Suzanna
- Caligo Telamonius
- Caligo teucer
- Caligo uranus
- Caligo zeuxippus
literature
- Philip J. De Vries: The butterflies of Costa Rica and their natural history . Princeton University Press, 1997, ISBN 0-691-08420-3 , pp. 245 ff .
Individual evidence
- ^ Lunau, K .: Warning, camouflaging, deceiving. Mimicry and other survival strategies in nature . Scientific Book Society, Darmstadt 2002.
- ↑ Koepke, J .: Species-specific patterns of camouflage coloring of carrion and faeces-eating day butterflies in the tropical rainforest of Peru . 1980 (diploma thesis University of Kiel).
- ↑ http://www.schmetterlingsfarm.de/schmetterlingsfarm/schmetterling-co/bananenfalter/?L=0 Info on Bananenfalter
- ↑ Caligo Hübner 1819. In: Tree of Life Web Project. The University of Arizona College of Agriculture and Life Sciences and The University of Arizona Library, October 1, 2006, accessed January 10, 2008 .
