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Lafranca Moth Article.Pdf What you may not know about... MScientific classificationoths Kingdom: Animalia Phylum: Arthropoda Class: Insecta Photography and article written by Milena LaFranca order: Lepidoptera [email protected] At roughly 160,000, there are nearly day or nighttime. Butterflies are only above: scales on moth wing, shot at 2x above: SEM image of individual wing scale, 1500x ten times the number of species of known to be diurnal insects and moths of moths have thin butterfly-like of microscopic ridges and bumps moths compared to butterflies, which are mostly nocturnal insects. So if the antennae but they lack the club ends. that reflect light in various angles are in the same order. While most sun is out, it is most likely a butterfly and Moths utilize a wing-coupling that create iridescent coloring. moth species are nocturnal, there are if the moon is out, it is definitely a moth. mechanism that includes two I t i s c o m m o n f o r m o t h w i n g s t o h a v e some that are crepuscular and others A subtler clue in butterfly/moth structures, the retinaculum and patterns that are not in the human that are diurnal. Crepuscular meaning detection is to compare the placement the frenulum. The frenulum is a visible light spectrum. Moths have that they are active during twilight of their wings at rest. Unless warming spine at the base of the hind wing. the ability to see in ultra-violet wave hours. Diurnal themselves, The retinaculum is a loop on the lengths. Ultra-violet wing patterns moths are active butterflies hold underside of the forewing. This occur more in nocturnal lepidoptera. during the day. their wings upright mechanism connects the forewing to Birds often utilize their ability to It is very difficult and folded together, the hind wing. Butterflies also have perceive ultra-violet light in search to differentiate perpendicular to fore and hind wings, although they for prey. The lack of ultra-violet moths from their backs. Most lack this wing-coupling mechanism. wing patterns in crepuscular and butterflies at a often moths will diurnal moths assist in attempts to glance because be found resting wings avoid predation. Reflection of ultra- they physically with their wings Moths are in the order lepidoptera, violet light in moth wings is usually resemble each draped down their which is latin for ‘scaly wing’. Moth associated with the colors in the other very closely. backs or spread wings are constructed of thin layers human visible spectrum like white, There are two ways to distinguish a moth out to the side. of a protein called chitin. The chitin is blue, and yellow, while dark colors from a butterfly; behavior and anatomy. anatomy covered with thousands of tiny scales, more often abosrb ultra-violet light. many smaller than .25mm wide. behavior Moths frequently have antennae Some types of scales have chemical that are feathery. Butterflies have slim pigments that produce brilliant The main way to know if you are looking antennae that are wider at the tips, colors. Other types are comprised at a butterfly or a moth is whether it is which resemble clubs. Some species mimicry The Bee Hawk moth has also adapted to mimic bees in appearance. If The Sphingidae species of moths may be the most gifted in their ability potential predators believe that they can defend themselves with to mimic other organisms. Hemaris diffinis, or Snowberry Clearwing stingers, they will be less likely attacked. moth (center picture), has evolved to closely resemble a bumble bee. The Other species of moths also use sound to avoid predation. Bats are one Snowberry clearwing moth gets its name because it loses the scales of the top predators of moths. They utilize echolocation to pinpoint prey on its wings shortly after the pupa stage due to its highly active flight in the dark by emitting high-pitched squeaks that reflect off the moth. The behavior. This moth hovers over flowers in full, creating a buzzing sound sound wave then passes back to the bat’s ears, allowing the bat to estimate with its wings, much like that of a hummingbird. They use their long proboscis the distance the wave travelled.To counteract this, many nocturnal moths to feed from nectar-rich plants, such as snowberry and honeysuckle. have evolved ear-like organs which can pick up the sound waves emitted Another Sphingidae species called the Dead-Head Hawk moth uses the by bats. Their nerve cells are so highly tuned that the displacement of the mimicry of bees to its advantage. They enter a hive whilst producing specialized eardrum the size of an atom will activate the ear. Low frequency background squeaks that sound a queen bee. Disguised as a queen, the Dead-Head Hawk noise that is harmless is ignored and leaves the ears tuned to the important moth absconds stolen honey away from the hive. ultrasonic echolocation sound waves of predators. above: compound eye, shot at 2x above: compound eye, SEM topographical backscattered image, 500x eyes Superposition compound eyes are composed of ommatidia (single simple All Lepidoptera have compound eyes), where a facet lens and crystalline eyes. Butterflies have apposition cone form the imaging optics. Several compound eyes, while moths have facets join to relay incident light to superposition compound eyes. a rhabdom, thus making them more In a superposition eye, light reaches sensitive to light than the apposition photoreceptors called rhabdom through compound eyes of butterflies. This several facet lenses. Rhabdom are ability allows the mostly nocturnal transparent, crystalline receptive structures moth to navigate in the dark with ease. that lie beneath the cornea that occurs in Refractive index gradients in the the central visual unit of the compound eye. crystalline cones causes the redirection They are rod-like and consist of interlocking of incident light. Spherical eye shape microvilli. Rhabdom contain pigment cells of combined with well focusing crystalline various kinds that act to regulate the amount cones in equal sized ommatidia in all of light that is received. Light rays pass eye parts results in the same spatial through a transparent cone which converges acuity throughout the compound eye. the rays onto the tip of the rhabdom. In conclusion, this information only Rhabdom are capable of resolving the strikes the surface of these complex wavelength and plane of polarization and intriguing creatures. You can of a light ray. Photons can only be continue to find fascinating facts detected if the light-sensitive area of throughout this diverse order of insects. Refernces: 1 - http://www.mothscount.org/text/17/amazing_moths.html the photopigment molecule is on the 2 - http://jeb.biologists.org/content/209/10/1904.long 3 - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1560070/ same plane of polarization of the photon. 4 - http://beheco.oxfordjournals.org/content/15/6/982.full 5 - http://science.howstuffworks.com/zoology/insects-arachnids/moth-versus- butterfly1.htm.
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