Hemileuca
Hemileuca eglanterina
Hemileuca is a genus of butterflies of the family of peacock moth ( Saturniidae ). "The Global Lepidoptera Names Index " of the Natural History Museum lists for the genus 27 species that have their distribution in North America. The moths are very popular due to their variable coloring and wing patterning and their unusual way of life, which form an adaptation to the hot and dry habitats, with butterfly collectors. Most butterflies fly during the summer and autumn. The eggs are laid in annular Located on stems or branches of the caterpillar food plants and winter, which is unusual for peacocks Spinner. This, however, the caterpillars can develop even before the hot summer of the following year to pupation, so that the moths emerge in the cooler late summer and autumn. The stinging hairs of the caterpillars cause a lasting from one day to longer than a week rash on contact. In favorable years, the caterpillars can occur in masses.
- 6.1 Notes and references
- 6.2 Literature
Features
The moths are strongly colored in shades of white, black, yellow and red, and are in their appearance even within a species very variable. In many species the abdomen end is colored red, which may serve the warning of predators. In other species, it is ringed yellow and black. The antennae of the males are simply pinnate. For all other species within the subfamily they are bipinnate, as well as in most species of the family of peacocks Spinner. The genitals see which of the genus Coloradia similar.
The caterpillars are black, dark red or dark brown, but develop with age a species-specific pattern. The extensions ( Scoli ) on the back of the abdomen are made short tufts or groups of spikes, which have no central shaft. This distinguishes them from the larvae of the closely related genus Automeris. In all types stinging hairs are formed.
Occurrence
The moths are found from southern Canada to Mexico, on the west and southwest of the United States, including the Great Basin. The core of the distribution, where they form the deserts, chaparral and mountain areas. Although some species are rare, they can occur locally common. In general, the populations of those species that inhabit the wide and open habitats of the Great Basin and deserts of the southwestern United States, widely scattered, but have high individual densities.
Way of life
The moths of most species fly around quickly in a non-uniform unpredictable flight. If the animals are disturbed while sitting in their rest, they lift their wings over the back and bend the abdomen down. Species with yellow and black ringed abdomen pulsate in addition with this body part, which resemble fortified Hymenoptera, for example, wasps, arises ( Müllerian mimicry ).
Flight times and caterpillars
The adults of most species fly in the summer or autumn. At high altitudes, they fly rather earlier in the year and are diurnal. The few nocturnal species are found primarily in desert areas where they fly in the early autumn, when the evening temperatures are still high enough. In most species overwinter the eggs, which then hatch the caterpillars in March or April. In a few species the caterpillars hatch at the beginning of the winter rains in Southern California or at the beginning of the summer rainfall in southeastern Arizona. The moths of the new generation hatch in most species a few months after pupation, some of the animals but can overwinter as a pupa. In particular, in the desert species is documented in rearing in captivity, that the dolls can be two to four years before the moths emerge. The types of eglanterina group have a two-year life cycle in the habitats they occupy high mountain areas with a short growing season. The eggs overwinter in the first year, the dolls in the second. Those same species evolve much faster when raising them under more favorable conditions. The diapause, however, induced by the daylight hours and to correlate hormone levels.
The development cycle in which the eggs overwinter, probably an adaptation to the short growing season in the populated arid habitats. The hatching in the spring caterpillars can immediately find food in perfect quality. They finish their development from the hot and dry summer and spend it in the pupal stage before the moths in the fall or late summer hatch back with milder temperatures. The diurnal activity of the moths bypassing the cold night temperatures, which in turn are necessary to interrupt the development of the eggs.
Food of the caterpillars
The most important food plants of the caterpillars are rose family ( Rosaceae ), Buckthorn family ( Rhamnaceae ), willow family ( Salicaceae ), Daisy Family ( Asteraceae), Honeysuckle ( Caprifoliaceae ), Sumac ( Anacardiaceae ), legumes ( Fabaceae ), grasses ( Poaceae ) and buckwheat family ( Polygonaceae ) and, depending on the type or species group of which only certain plant families are eaten. The species that inhabit dry habitats, develop on the dominant shrubby plants there.
Development
The females of all species lay their eggs in annular Located on a tree branch or a flower stem of the food plant. When living in deserts species whose food plants are small, the clutch comprise less than 24 eggs, but eating on shrubs, trees and herbaceous plant species include the scrim 50 to 200 eggs.
Initially, the caterpillars feed sociable sitting close together. Because of their dark color they efficiently absorb solar radiation, and the resulting increased body temperature accelerates the physiological development, particularly in the higher mountain areas. The caterpillars live through at least five stages, depending on the type and food plant, it can be six or seven. After the fourth stage, they live as a loner. If these animals are disturbed, they curl on and let yourself fall to the ground. The caterpillars are decimated by parasitoid flies and Hymenoptera. Sometimes up to 90 % of the population are parasitized caterpillars. Pupation occurs in all species between plant parts on the ground or in tufts of grass. However, finding the caterpillars loose soil before and burying themselves most to a depth of 10 to 20 centimeters.
Taxonomy and systematics
The great variability of the moths, especially within the eglanterina group, led to the description of many subspecies, taking into account the high variability of the distribution areas and their overlap are usually taxonomically not tenable, however.
The genus has been divided by some authors in the four sub- genera for which the distribution of the species, however, is problematic. For this reason Tuskes and Collins define the species groups tricolor, maia, electra, burnsi, chinatiensis and eglanterina, which should reflect the phylogenetic relationship better.
"The Global Lepidoptera Names Index " of the Natural History Museum lists the following species of the genus:
- Hemileuca tricolor (Packard, 1872)
- Hemileuca lex ( Druce, 1897)
- Hemileuca hualapai ( Neumoegen, 1883)
- Hemileuca rubridorsa Fields, 1874
- Hemileuca oliviae Cockerell, 1898
- Hemileuca sororius (H. Edwards, 1881)
- Hemileuca numa ( Druce, 1897)
- Hemileuca mexicana ( Druce, 1887)
- Hemileuca mania ( Druce, 1897)
- Hemileuca dyari ( Draudt, 1930)
- Hemileuca lares ( Druce, 1897)
- Hemileuca maia ( Drury, 1773)
- Hemileuca nevadensis Strech, 1872
- Hemileuca lucina H. Edwards, 1887
- Hemileuca grotei Hopffer, 1868
- Hemileuca diana Packard, 1874
- Hemileuca juno Packard, 1872
- Hemileuca electra Wright, 1884
- Hemileuca slosseri Peigler & Stone, 1989
- Hemileuca burnsi J. H. Watson, 1910
- Hemileuca neumoegeni (H. Edwards, 1881)
- Hemileuca chinatiensis ( Tinkham, 1943)
- Hemileuca Griffini Tuskes, 1978
- Hemileuca conwayae Peigler, 1985
- Hemileuca hera (Harris, 1841)
- Hemileuca nutalli ( Strecker, 1875)
- Hemileuca eglanterina ( Boisduval, 1852)