Pyrgus malvae, the grizzled skipper, is a butterfly species from the family Hesperiidae. It is a small skipper (butterfly) with a chequered pattern on its wings that appears to be black and white. This butterfly can be found throughout Europe and is common in central and southern regions of England. The butterfly prefers three major types of habitat: woodland, grassland, and industrial. Eggs are laid on plants that will provide warmth and proper nutrition for development. As larvae, their movement is usually restricted to a single plant, on which they will build tents, unless they move onto a second host plant. Larvae then spin cocoons, usually on the last host plant they have occupied, where they remain until spring. Upon emerging as adult butterflies, grizzled skippers are quite active during the day and tend to favour blue or violet-coloured plants for food. Males and females can be differentiated by the shape of their wings: males have slightly more angular wings, while females have a more rounded wing shape. Larvae are coloured green and light brown with darker brown stripes. Seitz describes malvae "The terminal row of white dots developed, at least on the hindwing. Underside of hindwing reddish, with distinct white dots, those of the subterminal band being rounded. Veins bordered with yellowish white or white. In ab. taras Bergstr.(86a) the white spots of the forewing are united to form bands; occurs singly among ordinary specimens.

Europe, Asia from the Mediterranean Sea to the Amur; Mongolia. — Larva yellowish grey, minutely dotted with greenish, the dots bearing short thin hairs, dorsal line darker, spiracles yellowish; in June and

October on Potentilla, Dipsacus, Strawberry, Raspberry, and other plants. The butterflies are on the wing in April and May and again from the end of July onwards, on sunny slopes, roads among fields and clearings in woods, being common everywhere in Central Europe.

Geographic range

Pygrus malvae can be found throughout Western Europe in northern Scandinavia, parts of Greece, and some of the Mediterranean Islands.

Habitat

Although grizzled skippers occupy three major forms of habitats, they tend to settle in environments with spring nectar plants, larval food plants (agrimony, creeping cinquefoil, wild strawberry, tormentil), ranker vegetation, and edges with scrub or woodland.

Life history

Egg

Eggs are mainly found on agrimony, creeping cinquefoil, and wild strawberry plants, which provide nourishment for larvae.

Enemies

Predators

Grizzled skippers belong in family Hesperiidae, but another group of butterflies (family Lycaenidae) uses the mechanism of wing expansion to produce vibrations and communicate with ants. Similar to this behavior, grizzled skippers also produce vibrations upon expanding their wings. This resembles the ‘ant-attendant’ behaviour that is specific to butterflies in the Lycaenidae. Ants are recognized as potential predators for lycaenid caterpillars, therefore, vibration signaling most likely functions as an anti-predatory survival mechanism. Similarly, grizzled skippers also exhibit this kind of vibratory communication. Although the behavior is absent during the caterpillar stage, grizzled skippers are able to produce vibrations upon wing expansion. Akin to lycaenids, grizzled skippers may use these vibrations as signals to communicate with ants and potentially as an attempt to temper aggression.

Mating behaviour

thumb|Mating behaviour of Pyrgus malvae

Female/male interactions

Pheromones

Grizzled skippers are known to contain organs called androconia that are responsible for producing chemicals within the thorax as well as the abdomen. They are found in males at the forewing costal fold. The organs release sex pheromones that can be used as a sexual recognition mechanism and drive evolution. The process involves the male first locating a female visually, then using low concentrations of the pheromones at a relatively close proximity to indicate its viability as a mate. While courting the female, male butterflies have specialized hairlike structures called ‘tibial tufts’ on their hind legs that can be used to steer these chemicals directly to the female. However, this chemical communication cannot be differentiated between P. malvae and P. malvoides, a close relative considered a subspecies of P. malvae and not separated by isolation reproductive barriers. Warmer summers are more favorable for the grizzled skipper and are positively correlated with the species. This could result from relationships between warmth and the success of the mother's ability to lay the egg as well as of larvae survival. Warmer climates also tend to hasten the development of larvae and allow for earlier onset of the pupal stage.

Physiology

Wing structure effect on flight behaviour

The wings of Pygrus malvae are only mildly adhesive, rough, and highly hydrophobic. These qualities prevent their wings from sticking to external surfaces, support their resistance to water damage, and allow the butterfly to self-clean its wings without risking desiccation. Additionally, these properties enable the grizzled skipper to avoid excess weight bearing, consequently promoting secure and efficient flight patterns.

Conservation

Concerns

Past

1- Decreased woodland clearings, unimproved grassland, scrub habitats

See also

  • List of butterflies of Great Britain

References

Literature

  • Brereton, T. M.; Bourn, N. A. D., and Warren, M. S. (1998). Species action plan. Grizzled Skipper.
  • Dover, J. W., T. H. Sparks, and J. N. Greatorex-Davies. "The importance of shelter for butterflies in open landscapes." Journal of Insect Conservation 1.2 (1997): 89–97.
  • Elfferich, Nico W. "Is the larval and imaginal signalling of Lycaenidae and other Lepidoptera related to communication with ants." Deinsea 4.1 (1998): 91–96.
  • Fang, Yan. "Anisotropic Characteristic of Insect (Lepidoptera) wing Surfaces." (2015).
  • Hammond, Nicholas, et al. Concise Butterfly & Moth Guide. Bloomsbury, 2014.
  • Hernández-Roldán, Juan L., et al. "Morphological and chemical analysis of male scent organs in the butterfly genus Pyrgus (Lepidoptera: Hesperiidae)." Organisms Diversity & Evolution 14.3 (2014): 269–278.
  • Jong, Rienk. Superspecies Pyrgus malvae (Lepidoptera: Hesperiidae) in the East Mediterranean, with notes on phylogenetic and biological relationships. Rijksmuseum van Natuurlijke Historie, 1987.
  • Kociková, Lenka, et al. "Is colour an important factor influencing the behaviour of butterflies (Lepidoptera: Hesperioidea, Papilionoidea)?." European Journal of Entomology 109.3 (2012): 403.
  • Krämer, Benjamin, et al. "Microhabitat selection in a grassland butterfly: a trade-off between microclimate and food availability." Journal of Insect Conservation 16.6 (2012): 857–865.
  • Pollard, E. "Temperature, rainfall and butterfly numbers." Journal of Applied Ecology (1988): 819–828.
  • Roy, David B., et al. "Butterfly numbers and weather: predicting historical trends in abundance and the future effects of climate change." Journal of Animal Ecology 70.2 (2001): 201–217.
  • Streitberger, Merle, and Thomas Fartmann. "Molehills as important larval habitats for the grizzled skipper, Pyrgus malvae (Lepidoptera: Hesperiidae), in calcareous grasslands." European Journal of Entomology 110.4 (2013): 643.
  • Wallisdevries, Michiel F., and Ivo Raemakers. “Does Extensive Grazing Benefit Butterflies in Coastal Dunes?” Restoration Ecology, vol. 9, no. 2, 2001, pp. 179–188., doi:10.1046/j.1526-100x.2001.009002179.x.
  • Lepiforum.de
  • Pyrgus malvae at Caterpillar Hostplants Database