![]() Some tropical larvae are thought to mimic snakes. When resting, the larva usually holds its legs off the surface and tucks its head underneath (praying position), which, resembling the Great Sphinx of Giza, gives rise to the name "sphinx moth". A pattern of diagonal slashes along the side is a common feature. Others are more conspicuously colored, typically with white spots on a black or yellow background along the length of the body. Many are cryptic greens and browns, and have countershading patterns to conceal them. Usually, their bodies lack any hairs or tubercules, but most species have a "horn" at the posterior end, which may be reduced to a button, or absent, in the final instar. Sphingid caterpillars are medium to large in size, with stout bodies. The relative magnitude of the two frequency responses enables the moth to distinguish rotation around the different principal axes, allowing for rapid course control during aerial maneuvers. The Coriolis forces cause deflections of the antennae, which are detected by the Johnston's organ at the base of each antenna, with strong frequency responses at the beat frequency of the antennae (around 25 Hz) and at twice the beat frequency. The antennae are vibrated in a plane so that when the body of the moth rotates during controlled aerial maneuvers, the antennae are subject to the inertial Coriolis forces that are linearly proportional to the angular velocity of the body. In studies with Manduca sexta, moths have dynamic flight sensory abilities due to their antennae. Ī number of species are known to be migratory, all in the Sphingini and Macroglossinae, and specially in the genera Agrius, Cephonodes, Macroglossum, Hippotion and Theretra. A few common species in Africa, such as the Oriental bee hawk ( Cephonodes hylas virescens), Macroglossum hirundo, and Macroglossum trochilus, are diurnal. Some species fly only for short periods either around dusk or dawn, while other species only appear later in the evening and others around midnight, but such species may occasionally be seen feeding on flowers during the day. The male may douse the female with a pheromone before mating. Females call males to them with pheromones. Also, all male hawkmoths have a partial comb of hairs along with their antennae. Only males have both an undivided frenular hook and a retinaculum. For example, in the African species Agrius convolvuli (the convolvulus or morning glory hawk moth), the antennae are thicker and wing markings more mottled in the male than in the female. In some species, differences in form between the sexes is quite marked. Prior to flight, most species shiver their flight muscles to warm them up, and, during flight, body temperatures may surpass 40 ☌ (104 ☏). Both males and females are relatively long-lived (10 to 30 days). Most are crepuscular or nocturnal, but some species fly during the day. Some sphingids have a rudimentary proboscis, but most have a very long one, which is used to feed on nectar from flowers. The thorax, abdomen, and wings are densely covered in scales. They have a frenulum and retinaculum to join hindwings and forewings. ![]() They lack tympanal organs, but members of the group Choerocampini have hearing organs on their heads. They have wingspans from 4 cm ( 1 + 1⁄ 2 in) to over 10 cm (4 in).Īntennae are generally not very feathery, even in males. Sphingids are some of the faster flying insects some are capable of flying at over 5.3 m/s (19 km/h). This is thought to have evolved to deal with ambush predators that lie in wait in flowers. ![]() Sphingids have been much studied for their flying ability, especially their ability to move rapidly from side to side while hovering, called "swing-hovering" or "side-slipping". This hovering capability is only known to have evolved four times in nectar feeders: in hummingbirds, certain bats, hoverflies, and these sphingids (an example of convergent evolution). Some hawk moths, such as the hummingbird hawk-moth or the white-lined sphinx, hover in midair while they feed on nectar from flowers, so are sometimes mistaken for hummingbirds. The family was named by French zoologist Pierre André Latreille in 1802. Their narrow wings and streamlined abdomens are adaptations for rapid flight. They are moderate to large in size and are distinguished among moths for their agile and sustained flying ability, similar enough to that of hummingbirds as to be reliably mistaken for them. ![]() ![]() It is best represented in the tropics, but species are found in every region. The Sphingidae are a family of moths ( Lepidoptera) called sphinx moths, also colloquially known as hawk moths, with many of their caterpillars known as “hornworms” it includes about 1,450 species. ![]()
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