45-482: Several, see text Ceratomia is a genus of hawkmoths (family Sphingidae). The genus was erected by Thaddeus William Harris in 1839. Species include: This Sphinginae -related article is a stub . You can help Misplaced Pages by expanding it . Hawkmoth The Sphingidae are a family of moths commonly called sphinx moths , also colloquially known as hawk moths , with many of their caterpillars known as hornworms . It includes about 1,450 species . It
90-404: A pollination syndrome known as "sphingophily". Some species are quite general in visitations, while others are very specific, with the plant only being successfully pollinated by a particular species of moth. Orchids frequently have such specific relations with hawk moths and very long corolla tubes. The comet orchid ( Angraecum sesquipedale ), a rare Malagasy flower with its nectar stored at
135-465: A button, or absent, in the final instar . Many are cryptic greens and browns, and have countershading patterns to conceal them. Others are more conspicuously colored, typically with white spots on a black or yellow background along the length of the body. A pattern of diagonal slashes along the side is a common feature. When resting, the caterpillar usually holds its legs off the surface and tucks its head underneath (praying position), which, resembling
180-461: A dead or dying caterpillar. The pupal stage lasts approximately 14–18 days under laboratory conditions (17 hours light, 7 hours dark, 27 °C). When reared on a short-day photoperiod (12 hours light, 12 hours dark), pupae enter a state of diapause that can last several months. During the pupal stage, structures of the adult moth form within the pupal case, which is shed during eclosion (adult emergence). Adult M. sexta have narrow wings with
225-658: A gene called cytochrome P450 6B46 (CYP6B46) that converts nicotine into a metabolite. About 0.65% of nicotine metabolites are transported from the gut to the hemolymph , where they are reconverted to nicotine and released into the air from the tobacco hornworm's spiracles. The emitted nicotine is used as a way to deter spiders, a practice known as “toxic halitosis.” In one study, tobacco hornworms that fed from nicotine-deficient plants or expressed low levels of CYP6B46 were more susceptible to wolf spider predation. Tobacco hornworm caterpillars emit short clicking sounds from their mandibles when they are being attacked. This sound production
270-542: A hawk moth] from tropical Africa ( [Xanthopan] morganii ) is seven inches and a half [19 cm]. A species having a proboscis two or three inches longer [8 cm] could reach the nectar in the largest flowers of Angraecum sesquipedale , whose nectaries vary in length from ten to fourteen inches [36 cm]. That such a moth exists in Madagascar may be safely predicted, and naturalists who visit that island should search for it with as much confidence as astronomers searched for
315-462: A small peripheral desensitization for salicin, concluding that Schoonhoven erred, and that habituation in this case is centrally mediated. Tobacco hornworms are considered pests because they feed on the upper leaves of tobacco plants and leave green or black droppings on the plants. As adults, they do not damage plants since they feed on nectar. Tobacco hornworm larvae prefer humid environments. When dehydrated, tobacco hornworm larvae will move towards
360-428: A source of water or to an area with a high relative level of humidity. They use their antennae to locate water to drink . Nicotine is poisonous to most animals that use muscles to move because nicotine targets the acetylcholine receptor at the neuromuscular junction . However, the tobacco hornworm is capable of metabolizing nicotine from the tobacco plant and using nicotine as a defense against predators. It possesses
405-503: A steroidal glycoside found in those particular plants (del Campo et al., 2001). Salicin is a distasteful phagodeterrent , found only in Salix spp. while caffeine is a phagodeterrent that is actually toxic. Schoonhoven 1969 found that M. sexta habituation to salicin is mediated by desensitization of the deterrence associated peripheral neurons and Glendinning et al. 1999 the same for caffeine. However Glendinning et al. 2001 find only
450-585: A vertical surface at night, and can last several hours, with the male and female facing in opposite positions, their posterior ends touching. After mating, females deposit their fertilized eggs on foliage, usually on the underside of leaves. Like Drosophila melanogaster , M. sexta is commonly used as a model organism for experiments. They are frequently studied in the laboratory due to their large size and relative ease of rearing. They may be reared on host plants, such as tobacco and tobacco relatives, tomato plants, or wheat-germ-based artificial diet. Their rearing
495-431: A wing span of approximately 100 mm. M. sexta moths are nectarivorous and feed on flowers, demonstrating a remarkable ability to hover. Adults are sexually dimorphic . Males are identifiable by their broader antennae and the presence of claspers at the end of the abdomen. Female moths are typically ready to mate one week after eclosion , and do so only once. Males may mate many times. Mating generally occurs on
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#1732854676781540-430: A year if weather conditions permit. Females lay translucent, greenish, flattened, smooth eggs, usually singly on the host plants. Egg development time varies highly, from three to 21 days. Sphingid caterpillars are medium to large in size, with stout bodies. They have five pairs of prolegs . Usually, their bodies lack any hairs or tubercules, but most species have a "horn" at the posterior end, which may be reduced to
585-580: Is a moth of the family Sphingidae present through much of the Americas . The species was first described by Carl Linnaeus in his 1763 Centuria Insectorum . Commonly known as the Carolina sphinx moth and the tobacco hawk moth (as adults) and the tobacco hornworm and the Goliath worm (as larvae), it is closely related to and often confused with the very similar tomato hornworm ( Manduca quinquemaculata );
630-451: Is best represented in the tropics , but species are found in every region. 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. Their narrow wings and streamlined abdomens are adaptations for rapid flight. The family was named by French zoologist Pierre André Latreille in 1802. Some hawk moths, such as
675-772: Is big enough for medical imaging modalities (like CT , MRI , or PET ) and used as a model in imaging and gut inflammation. It is used in a variety of biomedical and biological scientific experiments. It can be easily raised on a wheat-germ-based diet. The larva is large, and thus it is relatively easy to dissect it and isolate its organs. M. sexta has a short life cycle, lasting about 30 to 50 days. In most areas, M. sexta has about two generations per year, but can have three or four generations per year in Florida. M. sexta eggs are spherical, approximately 1.5 millimeters in diameter, and translucent green. They typically hatch two to four days after they are laid. Eggs are normally found on
720-533: Is consumed. When they start to "wander", they are about to pupate, so are placed in a pupation chamber. Pupation chambers are holes drilled into a wood board. The Manduca larvae are sealed in the chamber using a stopper and allowed to pupate. After pupation, the pupae are placed in a breeding or colony chamber to eclose . Providing a cup of sugar water and a tobacco (or related) plant will allow mated females to oviposit fertile eggs, which can then be reared. When fed an artificial diet, Manduca larvae do not consume
765-401: Is straightforward, provided they receive a long daylight cycle (e.g., 14 hours) during development to prevent diapause . Eggs are rinsed for one to five minutes in dilute household bleach for disinfection. Eggs are placed on diet cubes or host plants. The eggs hatch and develop at different speeds depending on temperature. The larvae are moved to a fresh diet or leaves as their food spoils or
810-417: Is thought to have evolved to deal with ambush predators that lie in wait in flowers. Sphingids are some of the faster flying insects ; some are capable of flying at over 5.3 m/s (19 km/h). They have wingspans from 4 cm ( 1 + 1 ⁄ 2 in) to over 10 cm (4 in). Sphingid's antennae are generally not very feathery, even in males. They lack tympanal organs , but members of
855-545: The Great Sphinx of Giza , gives rise to the name "sphinx moth". Some tropical larvae are thought to mimic snakes. Larvae are quick to regurgitate their sticky, often toxic, foregut contents on attackers such as ants and parasitoids . Development rate depends on temperature, and to speed development, some northern and high-altitude species sunbathe. Larvae burrow into the soil to pupate, where they remain for two to three weeks before they emerge as adults. In some sphingids,
900-466: The M. sexta caterpillar has seven white diagonal lines with a black border at the first seven abdominal segments, and the horn is red or green with a red tip. The M. quinquemaculata caterpillar has V-shaped white markings with no borders at all eight of its abdominal segments, and the horn is dark blue or black in color. During the larval stage, M. sexta caterpillars feed on plants of the family Solanaceae , principally tobacco, tomatoes and members of
945-502: The Sphingini and Macroglossinae , and specially in the genera Agrius , Cephonodes , Macroglossum , Hippotion and Theretra . In studies with Manduca sexta , moths have dynamic flight sensory capabilities due to their antennae. 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
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#1732854676781990-426: The heart (aorta), which is a long, pulsating vessel running along the length of the caterpillar's dorsal side. The heart becomes visible through the skin just as the caterpillar is reaching the end of the final instar. A common biological control for hornworms is the parasitic braconid wasp Cotesia congregata , which lays its eggs in the bodies of the hornworms. The wasp larvae feed internally and emerge from
1035-529: 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. 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 ). Sphingids have been studied for their flying ability, especially their ability to move rapidly from side to side while hovering, called "swing-hovering" or "side-slipping". This
1080-430: The larvae of both feed on the foliage of various plants of the family Solanaceae . The larvae of these species can be distinguished by their lateral markings: Tomato hornworms have eight V-shaped white markings with no borders; tobacco hornworms have seven white diagonal lines with a black border. Additionally, tobacco hornworms have red horns, while tomato hornworms have dark blue or black horns. A mnemonic to remember
1125-830: The xanthophyll -which is a yellow pigment- needed to produce their green coloration; instead they appear blue. On some diets, they have very little pigment and pigment precursors, so are a very pale blue-white. As vitamin A and other carotenoids are necessary for the visual pigments ( rhodopsin ), an artificial-diet-reared hornworm may have poor vision due to lack of carotenoids in the diet. Captive-bred hornworms fed on an artificial diet are often given to insectivorous exotic animals, such as certain reptiles, fish and small mammals. They are preferred over wild-collected hornworms, which may bioaccumulate poisonous substances found in dietary plants. Hornworms, though originally bred for laboratories, are also farmed for this purpose. They are often sold already packed into pods that include everything
1170-604: The angular velocity of the body. 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 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. Most species are multivoltine, capable of producing several generations
1215-400: The body to spin their cocoons . Parasitized hornworms are often seen covered with multiple white, cottony wasp cocoons, which are often mistaken for large eggs. A wasp species, Polistes erythrocephalus , feeds on hornworm larvae. Before the larva pupates, it goes through a stage called the pre-pupa, where it shrinks considerably and prepares to pupate. Often people mistake this stage for
1260-445: The bottom of a 30-centimetre-long (12 in) tube, was described in 1822 by Louis-Marie Aubert du Petit-Thouars , and later, Charles Darwin famously predicted there must be some specialized moth to feed from it: [ A. sesquipetale has] nectaries 11 and a half inches long [29 cm], with only the lower inch and a half [4 cm] filled with very sweet nectar [...] it is, however, surprising, that any insect should be able to reach
1305-509: The color of the breast and abdomen. The Sphingidae is sometimes assigned its own exclusive superfamily , Sphingoidea, but is alternatively included with the more encompassing Bombycoidea . Following Hodges (1971) two subfamilies are accepted, namely the Sphinginae and Macroglossinae . Around 1,450 species of hawk moths are classified into around 200 genera. Some of the best-known hawk moth species are: Manduca sexta Manduca sexta
1350-596: The female with a pheromone before mating. 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. A few common species in Africa, such as the Oriental beehawk ( Cephonodes hylas virescens ), Macroglossum hirundo , and Macroglossum trochilus , are diurnal . A number of species are known to be migratory, all in
1395-490: The food into very small bits. Some species can tolerate quite high concentrations of specific toxins. Tobacco hornworms ( Manduca sexta ) detoxify and rapidly excrete nicotine , as do several other related sphinx moths in the subfamilies Sphinginae and Macroglossinae , but members of the Smerinthinae that were tested are susceptible. The species that are able to tolerate the toxin do not sequester it in their tissues; 98%
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1440-758: The forewing, broader than in mainland specimens. Molecular clock models using either rate- or fossil-based calibrations imply that the Madagascan subspecies X. m. praedicta and the African subspecies X. m. morgani diverged 7.4 ± 2.8 Mya (million years ago), which overlaps the divergence of A. sesquipedale from its sister, A. sororium , namely 7.5 ± 5.2 Mya. Since both these orchids have extremely long spurs, longspurs likely existed before that and were exploited by long-tongued moths similar to Xanthopan morganii praedicta . The long geological separation of subspecies morgani and praedicta matches their morphological differences in
1485-431: The genus Datura . M. sexta has five larval instars, which are separated by ecdysis (molting), but may add larval instars when nutrient conditions are poor. Near the end of this stage, the caterpillar seeks a location for pupation , burrows underground, and pupates. This searching behavior is known as "wandering". The imminence of pupation—suggested behaviorally by the wandering—can be anatomically confirmed by spotting
1530-666: The group Choerocampini have hearing organs on their heads. They have a frenulum and retinaculum to join hindwings and forewings. The thorax, abdomen, and wings are densely covered in scales. Some sphingids have a rudimentary proboscis , but most have a very long one, which is used to feed on nectar from flowers. Most are crepuscular or nocturnal , but some species fly during the day. Both males and females are relatively long-lived (10 to 30 days). Prior to flight, most species shiver their flight muscles to warm them up, and, during flight, body temperatures may surpass 40 °C (104 °F). In some species, differences in form between
1575-544: The larva feeds on its normal diet of plant foliage, it ingests pigmentacious carotenoids , which are primarily yellow in hue. The resulting combination is green. Under laboratory conditions—when fed a wheat-germ-based diet—larvae are turquoise in color due to the lack of carotenoids in their diet. The caterpillar stage of the tobacco hornworm is quite similar in appearance to that of the closely related tomato hornworm . The larvae of these two species can however be readily distinguished by their lateral markings. Specifically,
1620-447: The larvae need, including food. Care is relatively easy, and animals seem to relish their bright color and flavor. M. sexta larvae grow up to 100 millimeters in length, reaching up to 20 grams. Due to their large size, they are used as alternative animal models for medical imaging modalities like computed tomography , magnetic resonance imaging , or positron emission tomography . Researchers around Anton Windfelder have established
1665-570: The larvae of M. sexta as an alternative animal model for chronic inflammatory bowel diseases or as an animal model for testing new contrast agents for radiology . Tobacco hornworms are facultative specialists; the larvae can grow and develop on any host plants. However, the larvae prefer solanaceous plants, such as tobacco and tomato plants. On these types of plants, larvae grow and develop faster. The lateral and medial sensilla styloconia (sensory receptors) on their mouthparts help them to identify solanaceous plants by recognizing indioside D ,
1710-449: The markings is tobacco hornworms have straight white lines like cigarettes, while tomato hornworms have V-shaped markings (as in "vine-ripened" tomatoes). M. sexta has mechanisms for selectively sequestering and secreting the neurotoxin nicotine present in tobacco. M. sexta is a common model organism , especially in neurobiology , due to its easily accessible nervous system and short life cycle. Due to its immense size M. sexta
1755-411: The nectar: our English sphinxes have probosces as long as their bodies, but in Madagascar, there must be moths with probosces capable of extension to a length of between 10 and 12 inches! [25 and 30 cm] Alfred Russel Wallace published a sort of " wanted poster " (properly, a drawing in a book) of what this lepidopteran might look like, and, concurring with his colleague, added: [The proboscis of
1800-410: The planet Neptune , – and they will be equally successful. The predicted sphingid was discovered 21 years later and described as a subspecies of the one African species studied by Wallace: Xanthopan morganii praedicta , for which, the subspecific name praedicta ("the predicted one") was given. The Madagascan individuals had a pink, rather than white, breast and abdomen and a black apical line on
1845-536: The pupa has a free proboscis, rather than being fused to the pupal case as is most common in the macrolepidoptera. They have a cremaster at the tip of the abdomen. Usually, they pupate off the host plant, in an underground chamber, among rocks, or in a loose cocoon. In most species, the pupa is the overwintering stage. Sphingid larvae tend to be specific feeders, rather than generalists. Compared to similarly sized saturniids , sphingids eat soft young leaves of host plants with small toxic molecules , and chew and mash
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1890-399: The sexes is quite marked. For example, in the African species Agrius convolvuli (the convolvulus or morning glory hawk-moth), males have thicker antennae and more mottled wing markings than females. Only males have both an undivided frenular hook and a retinaculum. Only males have a partial comb of hairs along with their antennae. Females attract males with pheromones . The male may douse
1935-403: The three thoracic segments bears a pair of true legs, and there is a pair of prolegs on the third, fourth, fifth, sixth, and last abdominal segments in all larval instars. The prothoracic segment bears one pair of spiracles , and additional pairs occur on each of the eight abdominal segments. The hemolymph (blood) of this species contains insecticyanin, a blue-colored biliprotein . When
1980-427: The underside of foliage, but can also be found on the upper surface. M. sexta larvae are bright green in color and grow up to 100 millimeters in length. The posterior abdominal segment is tipped with a dorsocaudal horn that earns them the name "hornworm". The final instar consists of a cylindrical body covered with fine hairlike setae . The head is equipped with a pair of ocelli and chewing mouthparts . Each of
2025-408: Was excreted. However, other species, such as Hyles euphorbiae and Daphnis nerii , do sequester toxins from their hosts, but do not pass them on to the adult stage. Most adults feed on nectar, although a few tropical species feed on eye secretions, and the death's-head hawkmoth steals honey from bees. Night-flying sphingids tend to prefer pale flowers with long corolla tubes and a sweet odor,
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