21-630: Grass skippers or banded skippers are butterflies of the subfamily Hesperiinae , part of the skipper family, Hesperiidae. The subfamily was established by Pierre André Latreille in 1809. With over 2,000 described species , this is the largest skipper butterfly subfamily and occurs worldwide except in New Zealand. About 50 percent of grass skippers live in the Neotropics . 137 species are native to North America. Around 38 species are native to Australia. Genera Ochlodes and Hesperia exist exclusively in
42-425: A crochet hook , while the typical butterflies have club-like tips to their antennae, and moth-butterflies have feathered or pectinate (comb-shaped) antennae similar to moths . Skippers also have generally stockier bodies and larger compound eyes than the other two groups, with stronger wing muscles in the plump thorax , in this resembling many moths more than the other two butterfly lineages do. Unlike, for example,
63-659: A blackish streak or patch of scent scales on their forewings. Many species of skippers look very alike. For example, some species in the genera Amblyscirtes , Erynnis (duskywings), and Hesperia (branded skippers) cannot currently be distinguished in the field even by experts. The only reliable method of telling them apart involves dissection and microscopic examination of the genitalia , which have characteristic structures that prevent mating except between conspecifics . The roughly 3500 species of skippers are now classified in these subfamilies: Iridescence Iridescence (also known as goniochromism )
84-603: A group of butterflies placed in the family Hesperiidae within the order Lepidoptera (moths and butterflies). They were previously placed in a separate superfamily, Hesperioidea ; however, the most recent taxonomy places the family in the superfamily Papilionoidea , the butterflies. They are named for their quick, darting flight habits. Most have their antenna tips modified into narrow, hook-like projections. Moreover, skippers mostly have an absence of wing-coupling structure available in most moths. More than 3500 species of skippers are recognized, and they occur worldwide, but with
105-430: Is also found in plants, animals and many other items. The range of colours of natural iridescent objects can be narrow, for example shifting between two or three colours as the viewing angle changes, Iridescence can also be created by diffraction . This is found in items like CDs, DVDs, some types of prisms , or cloud iridescence . In the case of diffraction, the entire rainbow of colours will typically be observed as
126-419: Is the phenomenon of certain surfaces that appear gradually to change colour as the angle of view or the angle of illumination changes. Iridescence is caused by wave interference of light in microstructures or thin films . Examples of iridescence include soap bubbles , feathers , butterfly wings and seashell nacre , and minerals such as opal . Pearlescence is a related effect where some or most of
147-508: The Arctiinae , though, their wings are usually small in proportion to their bodies. Some have larger wings, but only rarely as large in proportion to the body as in other butterflies. When at rest, skippers keep their wings usually angled upwards or spread out, and only rarely fold them up completely. The wings are usually well-rounded with more or less sharply tipped forewings. Some have prominent hindwing tails, and others have more angled wings;
168-682: The Holarctic . They are usually orange, rust, or brown in colour and have pointed forewings. Many species have dark markings or black stigmas on their forewings. Most members of this subfamily have an oval antenna club with an apiculus on the tip, although Carterocephalus and Piruna do not. The antennae generally has a sharp bend. Hesperiinae larvae feed on many different types of grasses and sedges and palms, though some species are limited. Adults typically visit flowers and hold their wings together while feeding. Hesperiinae are unique in that they hold their wings partially open while resting, with
189-582: The neon tetra is also iridescent. A single iridescent species of gecko, Cnemaspis kolhapurensis , was identified in India in 2009. The tapetum lucidum , present in the eyes of many vertebrates, is also iridescent. Iridescence is known to be present among prehistoric non-avian and avian dinosaurs such as dromaeosaurids , enantiornithes , and lithornithids . Muscle tissues can display irisdescence. Many groups of plants have developed iridescence as an adaptation to use more light in dark environments such as
210-453: The Neotropics, but recent phylogenetic analyses suggest the traditional Papilionoidea are paraphyletic , thus the subfamilies should be reorganised to reflect true cladistic relationships. Collectively, these three groups of butterflies share many characteristics, especially in the egg , larval , and pupal stages. Nevertheless, skippers have the antennae clubs hooked backward like
231-513: The case of pearlescence some or most of the light is white, giving the object a pearl -like luster. Artificial pigments and paints showing an iridescent effect are often described as pearlescent, for example when used for car paints . Eledone moschata has a bluish iridescence running along its body and tentacles . The feathers of birds such as kingfishers , birds-of-paradise , hummingbirds , parrots , starlings , grackles , ducks , and peacocks are iridescent. The lateral line on
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#1733094526249252-568: The diffraction signal is masked by the colouration due to plant pigments . In biological (and biomimetic ) uses, colours produced other than with pigments or dyes are called structural colouration . Microstructures, often multi-layered, are used to produce bright but sometimes non-iridescent colours: quite elaborate arrangements are needed to avoid reflecting different colours in different directions. Structural colouration has been understood in general terms since Robert Hooke 's 1665 book Micrographia , where Hooke correctly noted that since
273-425: The forewings and hindwings held at different angles. This is known as the "jet-plane position". Most male grass skippers perch to await females. Adults are strong fliers; they move quickly and usually in a linear direction. Some of the species, however, do flutter and these species patrol for females rather than perch. The following grass skippers are considered at risk. Skipper (butterfly) Skippers are
294-546: The goddess Iris of Greek mythology , who is the personification of the rainbow and acted as a messenger of the gods. Goniochromism is derived from the Greek words gonia , meaning "angle", and chroma , meaning "colour". Iridescence is an optical phenomenon of surfaces in which hue changes with the angle of observation and the angle of illumination. It is often caused by multiple reflections from two or more semi-transparent surfaces in which phase shift and interference of
315-550: The greatest diversity in the Neotropical regions of Central and South America. Traditionally, the Hesperiidae were placed in a monotypic superfamily Hesperioidea, because they are morphologically distinct from other Rhopalocera (butterflies), which mostly belong to the typical butterfly superfamily Papilionoidea . The third and rather small butterfly superfamily is the moth-butterflies (Hedyloidea), which are restricted to
336-403: The iridescence of a peacock 's feather was lost when it was plunged into water, but reappeared when it was returned to the air, pigments could not be responsible. It was later found that iridescence in the peacock is due to a complex photonic crystal . Pearlescence is an effect related to iridescence and has a similar cause. Structures within a surface cause light to be reflected back, but in
357-443: The lower levels of tropical forests. The leaves of Southeast Asia's Begonia pavonina , or peacock begonia, appear iridescent azure to human observers due to each leaf's thinly layered photosynthetic structures called iridoplasts that absorb and bend light much like a film of oil over water. Iridescences based on multiple layers of cells are also found in the lycophyte Selaginella and several species of ferns . Nanocellulose
378-505: The reflected light is white. The term pearlescent is used to describe certain paint finishes, usually in the automotive industry, which actually produce iridescent effects. The word iridescence is derived in part from the Greek word ἶρις îris ( gen. ἴριδος íridos ), meaning rainbow , and is combined with the Latin suffix -escent , meaning "having a tendency toward". Iris in turn derives from
399-490: The reflections modulates the incidental light , by amplifying or attenuating some frequencies more than others. The thickness of the layers of the material determines the interference pattern. Iridescence can for example be due to thin-film interference , the functional analogue of selective wavelength attenuation as seen with the Fabry–Pérot interferometer , and can be seen in oil films on water and soap bubbles. Iridescence
420-469: The skippers' basic wing shapes vary not much by comparison to the Papilionoidea, though. Most have a fairly drab coloration of browns and greys; some are more boldly black-and-white. Yellow, red, and blue hues are less often found, but some largely brown species are quite richly colored, too. Green colors and metallic iridescence are generally absent. Sexual dichromatism is present in some; males may have
441-429: The viewing angle changes. In biology, this type of iridescence results from the formation of diffraction gratings on the surface, such as the long rows of cells in striated muscle , or the specialized abdominal scales of peacock spider Maratus robinsoni and M. chrysomelas . Some types of flower petals can also generate a diffraction grating, but the iridescence is not visible to humans and flower-visiting insects as
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