Immature stages of blister beetles often go unnoticed. Convolvulaceae (Ipomoea) and Leguminosae (Bradburya, Coelosia) in the U.S. and these families and Bignoniaceae, Euphorbiaceae, and Verbenaceae in the West Indies. In the larval stage, blister beetles prey on the immature stages of solitary bees or on the eggs of grasshoppers in the family Acrididae (short horned grasshoppers), common grasshoppers in found pastures and grasslands. Crimpers can kill blister beetles and cause them to remain in the hay. Blister Beetles toxic effect on livestock, known ascantharidin toxicosis, is the greatest threat posed by blister beetles. Adult hosts: Clematis spp. P. sinuata (Olivier) - Coastal Plain from Mississippi to North Carolina; south in Florida to Highlands County. Most controls for feed and grass crops, including spraying, cant entirely eliminate the insects or the threat they pose. Proper identification of blister beetles in regards to various other kinds of non-toxic beetles that might resemble them, such as theasparagus beetle, is important toprotecting livestock and preventing crop damage. Zonitis cribricollis (LeConte) - Widely distributed in Florida, south to Dade County Achillea, Coreopsis, Helianthus, and Rudbeckia (Asteraceae). Adults feed, mate and females begin laying clusters of eggs in the soil. The chemical decreases blood calcium levels and irritates the stomach lining, small intestine, bladder, and urine tract. Orkin can provide the right solution to keep beetles in their placeout of your home. Often taken at lights. The wing covers are soft and flexible, and the legs are relatively long. Horses that have ingested cantharidin may exhibit symptoms of colic, including excessive salivation, diarrhea, bloody feces, sweating, dehydration, cramps, and frequent urination. Horses are particularly susceptible to the poisoning. Adult Nemognatha nemorensis Hentz, a blister beetle. Their numbers increase gradually in the growing seasons early months, and an observant gardener can keep them from doing much damage. Keep the rangeand numbers of beetles down by spreadingdiatomaceous eartharound threatened plants or using it as a barrier in raised beds or other small plots. Not common. Pinto JD. When haying, avoid using implements such as hay crimpers that may crush the insects. Blister Beetle Life Cycle: A = adult, E = egg, T = first instar or triungulin, FG = first grub phase, C = coarctate phase in instar six or seven, SG = second grub phase, P = pupa. Their bodies are tan to amber colored with three dark (black) stripes on each wing cover (elytron). Blister beetles spend the winter in the larval stage. The family Meloidae, the blister beetles, contains about 2500 species, divided among 120 genera and four subfamilies (Bologna and Pinto 2001). P. schaefferi ((Blatchley) - A taxonomically isolated species known only from Florida (Pinellas, Depending on the type of beetle, aslittle as four to six grams of dead insects can be lethal. Biological synthesis and function have been largely neglected.
Encourage themto visit and feed in your garden. The digestive tract of a horse can become highly inflamed, resulting in secondary infections and bleeding.
Growers of hay and feed crops should take allprecautions to monitor and prevent infestations. Spinosad breaks down into inert ingredients within two or so days when exposed to sunlight, keeping it out of the water supply. Proceedings of the U.S. National Musuem 111: 197-226. Suggest your neighbors do the same. First instar larvae of the family Nemognathinae found in flowers or attached to the hairs of bees are sometimes mistaken for those of Ripiphoridae. False blister beetles, Coleoptera: Oedemeridae, Adams CL, Selander RB.
Blister beetles are not an indoor infesting pest. The larvae ride back to the nest where they prey on the inhabitants of the nest. And heres anillustrated listof various blister beetles found in Florida thatcan also be found elsewhere in the U.S. Photograph by Lyle J. Buss, University of Florida. Massachusetts; probably statewide in Florida. All blister beetles, however, have the distinctive narrow neck which contrasts with the broader head and abdomen. Catholic University Press, Washington, D.C. 1112 pp. 1979). There are some 250 kinds of blister beetles, members of the familyMeloidae, spread across the U.S. Upon finding hosts on which the can feed, the larvae take on an increasingly grub-like appearance, before pupation in the spring. Figure 1. The eggs hatch in two weeks or less. It persists in dead beetles long after the hay they infested has been dried and baled. Blister beetles can create a serious health threat to horses or sheep when large numbers of blister beetles and toxic amounts of canthardin are ingested in hay or other plants that are used for livestock feed. Pigweed(Amaranthus spp.) The blistering on the individual shown in the photograph, while uncomfortable, was not painful. Phylogenetic studies of Meloidae (Coleoptera), with emphasis on the evolution of phorsey. Insects in the City, Scaramuzza LC. The striped blister beetle, Epicauta vittata, has the typical cylindrical body shape. Photograph by Sean McCann. April-June. Adult female Epicauta heterodera Horn, a blister beetle. Represented in Florida, where it occurs south to Highlands County, by the nominate, eastern race. Larvae reaching pupaestage in the fall can overwinter just beneath the soil. E. sanguinicollis (LeConte) - Known only from South Carolina, Georgia and Florida. Eggs are laid in masses in the ground or under stones (Meloinae) or on the food plants of adults (Nemognathinae). Represented in Florida, where it occurs commonly throughout the state except for the Keys, extreme southern Georgia and southeastern South Carolina by the "lemniscate" or southeastern coastal race (Adams and Selander 1979). (17 February 2017), Werner FG. Of the Florida species, Nemognatha punctulata LeConte (misidentified as Zonitis vittigera (LeConte)) has been found in a nest of a Megachile sp. Interestingly, it is not necessary to ingest the beetle in order to be affected, as hay contaminated with the bodily fluid of crushed beetles can be just as dangerous. Keep grass, weeds and other growth trimmed around the margins of your garden to remove the places where they might get started. Females typically mate and oviposit periodically throughout their adult lives. Florida Veterinary Journal 10: 11-13. Brush the beetles off plants into a small container with some soapy water. Hemolymph is often exuded copiously by reflexive bleeding when an adult beetle is pressed or rubbed. 2006, Sansome 2002). A revision of the genera. Photograph by John L. Capinera, University of Florida. Blister beetle infestations often occur at the edges of gardens or in surrounding vegetation. E. obesa (Chevrolat) - Southeastern Canada, south through eastern U.S., south to Veracruz and Oaxaca, Mexico. Cantharidin is also present in Spanish fly, a well-known aphrodisiac. California Medicine 93 11-12. Photograph by John L. Capinera, University of Florida. February-May. 182 pp. Adult hosts: Principally on cotton, okra, Asteraceae, Opuntia (Cactaceae), Ipomoea (Convolvulaceae), and Vigna (Leguminosae). Cicuta, Daucus, Eryngium, and several other Umbelliferae. Blister beetles are most likely to come into contact with homeowners as they are gardening, trimming shrubs or planting flowers, so wear protective gloves and long sleeve shirts to help prevent blister beetle exposure. Figure 10. Unless extensive, medical treatment beyond first aid for blistering on humans is probably not necessary. Photograph by Sean McCann. Figure 17. Our local Pros are the pest experts in your area. Theyre also found in the grasslands of the west and southwest, and in gardens along the Pacific coast. Photograph by Samuel Grubb. Gerardia (Scrophulariaceae). After feeding to repletion, the larva, through ecdysis, becomes scarabaeiform and enters a period of rapid growth (first grub phase, FG) that lasts until the end of instar five or six. Our customer care team is available for you 24 hours a day. E. torsa (LeConte) - Oklahoma and east Texas, east on the Coastal Plain to Georgia and north to Rare. Rarely, a larva pupates directly from the C phase. Adult hosts: Asteraceae, Schrankia (Leguminosae), Asteraceae, and cotton. Photograph by James Castner, University of Florida. Once they become adults, theyre nothing but trouble. Most adults eat only floral parts, but some, particularly those of Epicauta spp., eat leaves as well. N. piazata Fabricius - Represented in Florida by the nominate race (Mississippi to West Virginia south), which occurs statewide, including the Keys. Photograph by Lyle J. Buss, University of Florida. Adult Pyrota lineata (Olivier) a blister beetle. Breve nota acerca de dos parsitos de ", Schoeb TR, Panciera RJ. Several of the Florida blister beetles feed on cultivated plants. Most modern hay production equipment is equipped with crimpers which crimp alfalfa stems, shortening the drying time for the hay. In addition, horses differ in their sensitivity to cantharidin. Blister beetles. E. heterodera Horn - Southeastern U.S., coastal Mississippi to Georgia and south in Florida to Osceola County. Adult blister beetlesvary in size and coloring. Adult clematis blister beetle, Epicauta cinerea Forster, margined color form. Selander RB. Adult "Florida" blister beetle, Epicauta floridensis Werner. Figure 8. Photograph by Lyle J. Buss, University of Florida. Several Asteraceae and Gerardia (Scrophulariaceae). The blisters soon diminished on their own. Floating row coverslet in sun, water and air but keep bugs out! Recorded in Florida from Baker and Volusia counties south to Highlands County. Figure 3. Nemognathinae are unusual in that the SG larva and following pupa and adult are A key to Epicauta species is in Pinto (1991). Even though cantharidin is caustic, it has medical properties that people have long exploited in the form of Spanish fly. They feed on the flowers and leaves of a wide variety of plants, including those in the Amaranthaceae, Asteraceae, Fabaceae, and Solanaceae families, and can cause considerable defoliation to the plants on which they congregatein large numbers. Unfortunately, cantharidin can be fairly toxic and it is no longer widely used in medicine. (Its also helpful for maintaining proper soil pH.). Eggs are laid by the female in protected areas like under stones. Arnett Jr RH. P. mutata (Gemminger) - Northern Florida, including the panhandle, south to Polk County. But never handle blister beetles with bare hands. Read the product label directions and timeyour applications accordingly. Adult Nemognatha punctulata LeConte, a blister beetle. Presumably in response to adverse environmental conditions, larvae of several genera of Meloinae can return to the C phase after reaching the SG phase. Certain species may have up to 50 times more cantharidin than others. The concentration of cantharidin in beetles varies by species. It is most commonly taken on inflorenscences of Solidago. Species of Epicauta, particularly the margined blister beetle, E. funebris, and the striped blister beetle, E. vittata, often damage alfalfa, beet, potato, tomato, and other crops by defoliation. 1979. They get their name from a caustic chemical they produce called cantharidin. In this phase the musculature undergoes profound degeneration and respiration is reduced to an extremely low level, permitting survival for more than a year, if necessary. Adult margined blister beetle, Epicauta funebris Horn. Blisters resulting by smashing a single blister beetle on the neck. E. tenuis (LeConte) - South Carolina, Georgia, and Forida. Adult hosts: Ipomoea (Convolvulaceae), Schrankia (Leguminosae), and (in captivity) Solanum (Solanaceae). South Carolina Agricultural Experiment Station Technical Bulletin 1033: 1-124. Protects to26F. First cuttings, made before the beetles have increased their numbers, are generally safer than cuttings from later in the season. December-June. Come July, a garden can be suddenly overtaken by hordes of leaf-munching beetles. University of California Press. Since adults are gregarious and often highly colored, they tend to be conspicuous. Adult Epicauta floridensis Werner (left), and E. cinerea Forster (right). Kinney KK, Peairs FB, Swinker AM. Adult Epicauta stigosa (Gyllenhal), a blister beetle. These swarming garden and fieldpests contain a toxin that can severely injure livestock if swallowed. E. excavatifrons Maydell - Coastal Mississippi and Alabama, and south in Florida to Marion County. Photograph by Lyle J. Buss, University of Florida. Horses are particularly vulnerable to blister beetle poisoning. Learn safe, organic solutions for effective blister beetle control here. They will not stop early-season adults who over-winter as late-stage larvae in the soil. Enns WR. and Alachua counties to Hillsborough County. Blister beetles also do damage tograsshoppers, one of the most destructive farm and garden pests. Oyster shell lime can also be used as a barrier but is not an effective killer of beetles and functions mostly as a repellent.
Whether you suspect a blister beetle infestation or want to take necessary precautions to prevent that, here are the 12 things you can do to do effective blister beetle control: Frequent and careful inspection of home gardens can go a long way towardscontrolling beetle damage. When crushed, the beetle can literally bleed the chemical from its joints, and skin contact with it can result in blisters. They feed on eggs and stored food in the bee nest as they progress through several additional developmental stages, from larva to legless grub. One record at light. In instar six or seven, the larva typically becomes heavily sclerotized and immobile (coarctate phase, C). Contact with cantharidin causes blistering and tissue damage. Keep it out of your landscape entirely. Most species pass the winter or dry season as coarctate phase larvae, while a few do so as diapausing eggs, triungulin larvae, or adults. Bidens and "thistle" (Asteraceae). Various types ofthe beetle are commonin the east, south, and midwest. Blisters commonly occur on the neck and arms, as the result of exposure to adult beetles attracted to outdoor lights at night. The two stripes in the middle of the back continue onto the throrax and often onto the head. Two species occur both in the southeastern U.S. and the West Indies. A powerful, fast-acting formula made to provide broad spectrumrelief. Blister beetles, feeding in a hay field, may accidentally be ground up when the hay is harvested. The severity of the response depends on the amount of cantharidin swallowed, the size and health of the animal, and can range from temporary poisoning to decreased digestive function to death. The blistering agent is cantharidin, an odorless terpene (exo-1,2-cis-dimethyl-3,6-ep- oxyhexahydro-phthalic anhydride) occurring elsewhere only in beetles of the family Oedemeridae (Arnett 2008). In both groups, the body is navicular (boat-shaped) and heavily sclerotized and there is a definite pattern of setation. Photograph by James Castner, University of Florida. Cantharides is sometimes specified as the Eurasian Spanishfly, Lytta vesicatoria (Linnaeus). Blister beetles (Meloidae) are commonly confused with beetles in the family Oedemeridae (false blister beetles) (Arnett 2008) and the Tenebrionidae subfamily Lagriinae (long-jointed beetles). Meloid beetles (Coleoptera) of the West Indies. (March 2006). Eastern U.S., west to Texas and South Dakota and north to Massachusetts. 1969. Pseudozonitis longicornis (Horn) - Kansas and east Texas east along the Coastal Plain to South Always wear gloves. Humans who ingest the pest can expect severe damage to the urinary tract and gastrointestinal lining. Figure 5. Photograph by James Castner, University of Florida. The black blister is completely black. Most distributions and some host data are from Piinto (1991). The larvae of some Meloinae, including most Epicauta spp., prey on the eggs of acridid grasshoppers. They usually are seen during the day on flowers and also are attracted to lights at night.
When the pupal stage is complete, the newly emerged adult drops to the ground after nearly ten days and begins feeding on cultivated plants. Figure 13. Journal of Dermatological Treatment 20: 114-119. No species is indigenous. September-October. May-June. Eastern North America from Atlantic coast west to the Great Plains, southern Canada south to Texas and the Gulf Coast. We will help you find the right treatment plan for your home. Kirk VM. Size: Blister beetles are softbodied beetles that range in size from 1 to 2.5 cm in length. Ironweed (Vernonia spp.) However, other genera, particularly Mylabris and Epicauta, have been more commonly used, especially for extraction of cantharidin. Adult hosts: Helenium and other Asteraceae. Body length generally ranges between 3/4 and 2 cm in the Florida species. Keys to genera for adult beetles (Arnett 1960) and triungulin larvae (MacSwain 1956) are given in references. Most poisonings in Florida result from importation of alfalfa hay from western states experiencing grasshopper population outbreaks (Capinera, personal communication). There are several species of blister beetles in the U.S.
Larval development is hypermetamorphic, with four distinct phases. Florida has 26 species, only a small fraction of the total number in the U.S., but nearly three times that of the West Indies (Selander and Bouseman 1960). Texas A&M Veterinary Medical Diagnostics Laboratory, Texas A&M College of Agrculture and Life Sciences, Insect and Mite Pests of Commercial Pecans, http://texashighplainsinsects.net/insect-of-the-week/2013/5/21/blister-beetles-may-24-2013, https://texasinsects.tamu.edu/hemiptera/blister-beetle/. Selander RB, Bouseman JK. If you noticed beetles in your fields, let cut hay lie for two or more days to allow them time to abandon the hay. August-October. Cantharidin is toxic if swallowed. Nemognathine larvae are distinctive in having one to two (not four to five) stemmata on each side of the head, an ecdysial line on the thorax, and no pulvilli (bladderlike appendages). Blister beetles are sometimes a problem for field crops like alfalfa, sweet clover, canola, dry beans, soybeans, potatoes, and sugar beets. At lights. Figure 7. St. Johns, and Volusia counties) and Myrtle Beach, South Carolina (Kirk 1969). Adults, however, can be observed on vegetation. E. strigosa (Gyllenhal) - From eastern Texas to the Atlantic and then north along the coast to Massachusetts, probably statewide in Florida. In Florida, recorded in Alachua, Citrus, Sumter, and Brevard counties.
Keep an eye on children who put things in their mouth if blister beetles may be present. There are some 7,500 species worldwide and about 100 species in Texas http://texashighplainsinsects.net/insect-of-the-week/2013/5/21/blister-beetles-may-24-2013 . April-May. Adult male Epicauta heterodera Horn, a blister beetle. Nemognatha nemorensis Hentz - North Florida, south to Pinellas and Brevard counties. Adult hosts: Recorded on Clematis in all regions; and Amaranthus, alfalfa, Tribulas and tomato in Oklahoma and Arkansas. Respect them by not using sprays or chemicals that mightdo themharm. Figure 6. In addition to the threat presented by its toxicity, the beetle doesdamage to both garden and commercial plants, consuming a variety of leaf crops, plant blossoms, landscape flowers, and hay crops. Twelve species are more or less widely distributed in the central and/or eastern states. If disturbed, blister beetles may secrete a bodily fluid called cantharidin, which is a chemical that can cause irritation, swelling and blistering when it contacts human skin. They usually work in large clusters, gathered on the edge of potato patches and lettuce rows. At lights. Adult hosts: commonly on Leguminosae, including alfalfa, Baptisia, bean, pea, and sweetclover; sometimes attacks potato and glandless cotton. Ray AC, Tamulinas SH, Reagor JC. https://texasinsects.tamu.edu/hemiptera/blister-beetle/. Adults begin laying clusters of eggs in mid to late spring and continue through most of the season. Pyrota limbalis LeConte - Washington, D.C., south to Highlands County, Florida. will also draw beetles. Northern Florida, including the panhandle, south to Highlands County.
Although the toxicity of cantharidin to horses has not been conclusively determined, the estimated lethal dose ranges from 0.5 to 1 mg of cantharidin per 2.2 lbs of horsebody weight. http://agrilife.org/lubbock/files/2017/08/Managing-Insect-Pests-of-Texas-Forage-Crops-ENTO-064-2017.pdf, http://entnemdept.ufl.edu/creatures/urban/medical/blister_beetles.htm, http://entnemdept.ufl.edu/creatures/veg/potato/striped_blister_beetle.htm. The University of Illinois Crop Sciences division has illustrations of these four common typeshere(notice how tightly their wing covers come together). 2006, Mackay and Wollenman 1981, Schoeb and Panciera 1979) have revived interest in the pathology of cantharidin toxicosis and led to the development of a highly sensitive technique for detection of the compound (Ray et al. Recorded in Florida only from the Keys and Dade County. A lethal dosage causes fever, depression, shock, and death. When development resumes the muscles regenerate and, through ecdysis, the larva once again becomes scarabaeiform (second grub phase, SG); at this point it may or may not excavate a pupal chamber. N. punctulata LeConte - Bahama and Cayman islands, Cuba, Jamaica, and the southeastern U.S. The hemolymph (blood) of blister beetles contains a blistering substance called cantharidin.
The secretion containsablistering agent known as cantharidin, a substance used totreat the lesions caused by pox virus. 1981. Probably statewide in Florida. Blister beetles receive their common name from the ability of their hemolymph to produce blistering on contact with human skin. Most adults feed only on flower parts, but some eat leaves as well. Part I - Northern Coastal Plain. Evidence for a third type of larval prey in blister beetles (Coleoptera: Meloidae). Adult hosts: Ilex (Aquifoliaceae), Sapindus (Sapindaceae), and Albizzia, Amorpha, and Robinia (Leguminosae). Epicauta vittata can be found in the eastern U.S. and Canada. In at least some species, females receive large quantities of cantharidin from males during copulation. Adults are soft-bodied, long-legged beetles with the head deflexed, fully exposed, and abruptly constricted behind to form an unusually narrow neck, the pronotum is much narrower at the anterior end than the posterior and not carinate (keeled) laterally, the forecoxal cavities open behind, and (in all Florida species) each of the tarsal claws cleft into two blades.
Protect your home or business from blister beetles by learning techniques for identification and control.
Adult beetles are phytophagous, feeding especially on plants in the families Amaranthaceae, Asteraceae, Leguminosae, and Solanaceae. Adult hosts: unknown. E. fabricii (LeConte) - the ashgray blister beetle. Adult Pyrota lineata (Olivier) a blister beetle. 1945. The prothorax between the head and the body is narrow and resembles a neck. University of Kentucky Entomology. Northern Florida, including the panhandle, south to Indian River County Adult hosts: Many Leguminosae and Solanaceae, including alfalfa, beet, eggplant, potato, soybean, sugar beet, and tomato. Larvae of most genera enter the nests of wild bees, where they consume both immature bees and the provisions of one or more cells. While uncomfortable, no medical treatment was implemented and the blisters soon diminished on their own. Adult Epicauta pensylvanica (De Geer), the black blister beetle. Epicauta batesii Horn - Eastern and southeastern U.S., from New Jersey to southern Florida and west to Mississippi. An outbreak of blister beetle poisoning in horses in Florida. Reported damaging grapefruit flowers in Puerto Rico. The Taxonomy of North American. Blister beetles are typically not serious insect pests and only sometimes cause crop damage under specificconditions. The eyes are black or dark grey. Horses and livestock also may be affected. Has been taken in large numbers at lights. They tend to be more of an agricultural/livestock pest. If shaken from plants, the beetles will often lie in the dirt and play possum rather than scurry away. When beetles are alarmed or disturbed, they secrete blood and cantharidin. Several Asteraceae, including Bidens, Erigeron, Heterotheca, and, particularly, Rudbeckia. Entomology Volume 12. This is especially important in hay crops grown for feed. Color: Adults range in color from an ash gray to bright yellow with black stripes. Photograph by Lyle J. Buss, University of Florida.
Adult blister beetles live for over three months, and populations can expand rapidly in warm areas. Coloring can be bright and variegated, striped or flat. Well-anchored row covers can keep migrating beetles off your plants in the mid to late summer. Blister beetles pose a potential threat if horse owners use alfalfa as a source of hay. Adult hosts: Wide variety of plants, including Amaranthaceae (Amaranthus), Solanaceae (Solanum)and Fabaceae (Medicago, alfalfa), and such crops as bean, beet, cotton, potato, and tomato. Blister beetles are a common field and garden pest best known for the welt-raising secretion they release when injured or crushed. P. pallida Dillon - Oklahoma and east Texas east to Florida, where it extends south through Dixie Blister beetles (Coleoptera: Meloidae) are named for the cantharidin toxin found in their bodily fluids, which can induce blisters on human skin and life-threatening inflammations in horses and animals. Beetles are from 1/3 to 2/3 inches long. There have been cases where people living adjacent to tracts of pasture or grassland have been inundated with blister beetles, so it is not necessary to have alfalfa or other host crops present in order to have a significant blister beetle infestation. People would consume a concoction of dried and crushed blister beetles for ailments such as gout and arthritis, as well as using it as the aphrodisiac Spanish fly. A third, weaker faunal link with the West Indies is represented by Pseudozonitis longicornis (Horn), which belongs to a group including one West Indian species and two relictual species in east Texas (Enns 1956, Selander and Bouseman 1960). Orkins exclusive A.I.M. Birds will take blister beetles right off your plants. Figure 11. Journal of the Kansas Entomological Society 54: 757-783. Adult Epicauta fabricii (LeConte), the ashgray blister beetle. Cantharidin or cantharides (dried, pulverized bodies of adult beetles) was once employed extensively in human and veterinary medicine, primarily as a vesicant and irritant and is still used in the U.S. as the active ingredient in a proprietary wart remover (Epstein and Epstein 1960, Kartal Durmazlar et al, 2009). Its best to remove as many beetles and the plants theyve damaged as soon as theyre spotted and before they spread. Use them if you notice clusters of beetles (or expect them) in and around your garden come July. Taken internally or absorbed through the skin, cantharidin is highly toxic to mammals. In mid and late summer, they can arrive in swarms, seemingly overnight and because of their numbers, will do great damage in a short time. Hand-picking can be effective in home gardens, particularly when their numbers are low. is highly attractive to adult beetles. Unfortunately, cantharidin is a very stable compound that stays toxic to livestock even when the dried remains of beetles that have been killed during harvesting are fed with forage. Care should be taken when buying hay as well. The cantharidin impregnates the hay and can be consumed by the animals, potentially resulting in their death. September-November. Adults commonly live three months or more. High pressure liquid chromatographic determination of cantharidin, using a derivatization method in specimens from animals acutely poisoned by ingestion of blister beetles, Sansome D. (May 2002).