Hesperia comma, the silver-spotted skipper or common branded skipper, is a butterfly of the family Hesperiidae. The species is known as silver-spotted skipper in Europe and common branded skipper in North America where the butterfly Epargyreus clarus, a spread-winged skipper, also has the common name of "Silver-Spotted Skipper". Originally the species was known as the Pearl Skipper but as time went on the name Silver-Spotted Skipper began being ascribed to it more frequently. There are numerous subspecies spread throughout the world in Asia, Europe, and North America. The species has at least 15 subspecies in North America. In the UK they are rare, usually only found in the chalk hills of the Southern UK and are believed to have arrived in the UK either in the Late Glacial Period or the Holocene. As adults they have white tips with yellowish-white spots. They typically live for a year with most of their life spend overwintering as eggs for 7 months until temperatures warm in the spring. The larvae typically grow up in grazed areas with not too much overgrown vegetation and feed on host plants such as Sheep's Fescues (Festuca ovina). The larvae form tents made of silk and grass blades and as they pupate form cocoon-like structures out of the same materials near the ground. They emerge as adults in July through September. In the UK the species was facing decline, however due to restoration efforts and global warming their populations have begun to grow again.
Appearance
Often confused with the Large skipper Ochlodes sylvanus, this species is easily distinguished by the numerous white spots on the underside hindwings, and the tips of the upper forewings tend to be darker than those of the Large Skipper. The upper side is very similar to the Large Skipper however its spots are often more yellow. The dorsal side of the wings typically are orange and dark brown on the edge of the wings. The ventral side is often a green or olive color. The white spots are slightly more pale on females. Females tend to be larger than the males. While its wings are the most notable feature, the thorax and abdomen actually make up 70% of the body mass of most specimens. The thorax mass allows the butterflies to have more flight muscles permitting them to fly between habitat patches separated by large distances.
Distribution The silver-spotted skipper prefers warm calcareous sites and has a wide distribution as far south as North Africa, northwards throughout Europe to the Arctic and eastwards across Asia to China and Japan. In the UK they are only found in chalk downlands and are difficult to find outside of certain regions in the South. In North America the species is mostly concentrated to the west coast as the Sierra Nevada and Transverse Ranges act as barriers making it difficult for populations to migrate east.
Taxonomy Silver-Spotted Skippers belong to the genus Hesperia of the family Hesperiidae. Hesperia colorado was once considered a subspecies of Hesperia comma. Later studies found that Hesperia colorado was its own unique species leading to many subspecies once under Hesperia comma to be moved to the new species Hesperia colorado.
Genome and genetic diversity Hesperia comma's genome sequence is 525.3 megabases. Gene annotation found that 18,725 genes code for proteins. The mitochondrial genome is 17.73 kilobases. North American populations have been found to have more genetic diversity than Eurasian populations.
Subspecies Hesperia comma assiniboia (Lyman 1892) – Occupies the prairies from Alberta to Manitoba and south into North Dakota. Hesperia comma benuncas (Oberthur 1912) Hesperia comma borealis (Lindsey 1942) – Labrador branded skipper. This species is only found in Labrador in Canada. Hesperia comma catena (Staudinger 1861) Hesperia comma dimila (Moore 1874) Hesperia comma greenhornensis (Scott 2021) – Found in southern Sierra Nevada in California. Hesperia comma hulbirti (Lindsey 1939) – Hulbirt's branded skipper. This species has so far only been observed in the Olympic National Park in Washington. Hesperia comma laurentina (Lyman 1892) – Laurentian branded skipper. Found in the northeastern U.S. and eastern Canada. Hesperia comma lena Korshunov & P. Gorbunov 1995 Hesperia comma manitoba (Scudder 1874) – Manitoba branded skipper. Found primarily in the Pacific Northwest of America. Particularly Alaska south to Washington and east to the Great Slave Lake region in Canada, northwestern Wyoming and Colorado. Hesperia comma mixta (Alpheraky 1881) Hesperia comma pallida (Staudinger 1901) Hesperia comma planula (Korshunov 1995) Hesperia comma shandura (Evans 1949) Hesperia comma sushinki (Korshunov 1995) Hesperia comma tildeni (Freeman 1956) – Tilden's Skipper. Found in the inner coastal ranges of central California from Lake County to San Luis Obispo. Hesperia comma yosemite (Leussler 1933) – Occupies the western slopes of the Sierra Nevada in California.
Life cycle
Egg Females are univoltine, laying eggs only once a year. Females lay eggs during August and September in areas with short turf, up to 4 cm, usually around ant mounds, such as those of Lasius flavus. The ant hills provide a more open space with less dense vegetation, providing a favorable environment for the larvae. Often since the eggs are laid in heavily grazed areas many eggs are eaten by animals. Females also tend to choose areas with warm microclimates as larvae prefer warm temperatures. Typically eggs are laid on host plants such as Festuca ovina (Sheep's Fescues) in the UK. Outside the UK, females in places such as Oregon in the U.S. lay their eggs on Festuca roemeri (Roemer's Fescues) plants that are around 1-5 cm tall. A female will typically only lay one egg per leaf. Sometimes a great number of eggs can be found on one host plant. The eggs are a pale cream color or pearl white. This species overwinters as an egg for around 7 months and hatches in March through April.
… excerpt ends here. Continue reading the full article.
