Blister beetles are

beetle Beetles are insects that form the Taxonomic rank, order Coleoptera (), in the superorder Holometabola. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 40 ...

s of the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Meloidae, so called for their defensive secretion of a blistering agent,

cantharidin Cantharidin is an odorless, colorless fatty substance of the terpenoid class, which is secreted by many species of blister beetles. Its main current use in pharmacology is treating molluscum contagiosum and warts topically. It is a burn agent ...

. About 7,500

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

are known worldwide. Many are conspicuous and some are aposematically colored, announcing their toxicity to would-be

predator Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common List of feeding behaviours, feeding behaviours that includes parasitism and micropredation ...

Description

Blister beetles are hypermetamorphic, going through several larval stages, the first of which is typically a mobile

triungulin A planidium is a specialized form of insect larva seen in the first-instar of a few families of insects that have parasitoidal ways of life. They are usually flattened, highly Sclerotization, sclerotized (hardened), and quite mobile. The functi ...

. The

larva A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...

e are

insectivorous A robber fly eating a hoverfly An insectivore is a carnivorous animal or plant which eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects. The first vertebrate insectivores we ...

, mainly attacking bees, though a few feed on

grasshopper Grasshoppers are a group of insects belonging to the suborder Caelifera. They are amongst what are possibly the most ancient living groups of chewing herbivorous insects, dating back to the early Triassic around 250 million years ago. Grassh ...

eggs. While sometimes considered

parasitoid In evolutionary ecology, a parasitoid is an organism that lives in close association with its host (biology), host at the host's expense, eventually resulting in the death of the host. Parasitoidism is one of six major evolutionarily stable str ...

s, in general, the meloid larva apparently consumes the immature host along with its provisions, and can often survive on the provisions alone; thus it is not an obligatory parasitoid, but rather a facultative parasitoid, or simply a

kleptoparasite Kleptoparasitism (originally spelt clepto-parasitism, meaning "parasitism by theft") is a form of feeding in which one animal deliberately takes food from another. The strategy is Evolutionarily stable strategy, evolutionarily stable when stealin ...

. The adults sometimes feed on flowers and leaves of plants of such diverse families as the

Amaranthaceae Amaranthaceae ( ) is a family of flowering plants commonly known as the amaranth family, in reference to its type genus '' Amaranthus''. It includes the former goosefoot family Chenopodiaceae and contains about 165 genera and 2,040 species, maki ...

Asteraceae Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchi ...

Fabaceae Fabaceae () or Leguminosae,International Code of Nomen ...

, and

Solanaceae Solanaceae (), commonly known as the nightshades, is a family of flowering plants in the order Solanales. It contains approximately 2,700 species, several of which are used as agricultural crops, medicinal plants, and ornamental plants. Many me ...

. Cantharidin, a poisonous chemical that causes blistering of the skin, is secreted as a defensive agent. It is used medically to remove warts and is collected for this purpose from species of the genera '' Mylabris'' and '' Lytta'', especially ''

Lytta vesicatoria ''Lytta vesicatoria'', also known as the Spanish fly, is an aposematic emerald-green beetle in the blister beetle family (Meloidae). It is distributed across Eurasia. The species and others in its family were used in traditional apothecary p ...

'', better known as "Spanish fly".

Toxicity

Cantharidin is the principal irritant in " Spanish fly", a folk medicine prepared from dried beetles in the family Meloidae. The largest genus, '' Epicauta'', contains many species toxic to horses. A few beetles consumed in a single feeding of

alfalfa Alfalfa () (''Medicago sativa''), also called lucerne, is a perennial plant, perennial flowering plant in the legume family Fabaceae. It is cultivated as an important forage crop in many countries around the world. It is used for grazing, hay, ...

hay may be lethal. In semiarid areas of the western United States, modern harvesting techniques may contribute to cantharidin content in harvested forage. The practice of hay conditioning, crushing the stalks to promote drying, also crushes any beetles present and causes the release of cantharidin into the fodder. Blister beetles are attracted to alfalfa and weeds during bloom. Reducing weeds and timing harvests before and after bloom are sound management practices. Using equipment without hay conditioners may reduce beetle mortality and allow them to escape before baling.

Evolutionary history

The family is thought to have begun diversifying during the

Early Cretaceous The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 ...

. The oldest fossil of the group is a larva (triangulin) found

phoretic Phoresis or phoresy is a temporary Commensalism, commensalistic relationship when an organism (a phoront or phoretic) attaches itself to a host organism solely for travel. It has been seen in tick, ticks and mite, mites since the 18th century, ...

on a schizopterid bug from the mid Cretaceous

Burmese amber Burmese amber, also known as Burmite or Kachin amber, is amber from the Hukawng Valley in northern Myanmar. The amber is dated to around 100 million years ago, during the latest Albian to earliest Cenomanian ages of the mid-Cretaceous period. Th ...

, dated to around 99 million years ago.

Systematics

Subfamily Eleticinae

Tribe Derideini *'' Anthicoxenus'' *'' Deridea'' *'' Iselma'' *'' Iselmeletica'' Tribe Morphozonitini *'' Ceriselma'' *'' Morphozonitis'' *'' Steniselma'' Tribe Eleticini *'' Eletica'' Tribe Spasticini *'' Eospasta'' *'' Protomeloe'' *'' Spastica'' *'' Xenospasta''

Subfamily Meloinae

Tribe Cerocomini *'' Anisarthrocera'' *'' Cerocoma'' *'' Diaphorocera'' *'' Rhampholyssa'' *'' Rhampholyssodes'' Tribe Epicautini *'' Denierella'' *'' Epicauta'' *'' Linsleya'' *'' Psalydolytta'' Tribe Eupomphini *'' Cordylospasta'' *'' Cysteodemus'' *'' Eupompha'' *'' Megetra'' *'' Phodaga'' *'' Pleropasta'' *'' Tegrodera'' Tribe Lyttini *'' Acrolytta'' *'' Afrolytta'' *'' Alosimus'' *'' Berberomeloe'' *'' Cabalia'' *'' Dictyolytta'' *'' Eolydus'' *'' Epispasta'' *'' Lagorina'' *'' Lydomorphus'' *'' Lydulus'' *''

Lydus Lydus (Ancient Greek: Λυδός), a son of Atys and Callithea, grandson of Manes, and brother of Tyrrhenus or Torybus, is a legendary figure of the 2nd millennium BC who is attested by Herodotus to have been an early king of Lydia, then prob ...

'' *'' Lytta'' *'' Lyttolydulus'' *'' Lyttonyx'' *'' Megalytta'' *'' Muzimes'' *'' Oenas'' *'' Parameloe'' *'' Paroenas'' *'' Physomeloe'' *'' Prionotolytta'' *'' Prolytta'' *'' Pseudosybaris'' *''

Sybaris Sybaris (; ) was an important ancient Greek city situated on the coast of the Gulf of Taranto in modern Calabria, Italy. The city was founded around 720 BC by Achaeans (tribe), Achaean and Troezenian settlers and the Achaeans also went on ...

'' *'' Teratolytta'' *'' Tetraolytta'' *'' Trichomeloe'' Tribe Meloini *'' Cyaneolytta'' *'' Lyttomeloe'' *'' Meloe'' *'' Spastomeloe'' *'' Spastonyx'' Tribe Mylabrini *'' Actenodia'' Meloidae Actenodia CMR beetle 3491

*'' Ceroctis'' *'' Croscherichia'' *'' Hycleus'' *'' Lydoceras'' *'' Mimesthes'' *'' Mylabris'' *'' Paractenodia'' *'' Pseudabris'' *'' Semenovilia'' *'' Xanthabris'' Tribe Pyrotini *'' Bokermannia'' *'' Brasiliota'' *'' Denierota'' *'' Glaphyrolytta'' *'' Lyttamorpha'' *'' Picnoseus'' *'' Pseudopyrota'' *'' Pyrota'' *'' Wagneronota'' Genera ''

incertae sedis or is a term used for a taxonomy (biology), taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty ...

'' *'' Australytta'' *'' Calydus'' *'' Gynapteryx'' *'' Oreomeloe'' *'' Pseudomeloe''

Subfamily Nemognathinae

Tribe Horiini *'' Cissites'' *''

Horia Horia or Horea may refer to: Places in Romania Communes *Horea, Alba Horea (formerly ''Arada''; ; ) is a Commune in Romania, commune located in Alba County, Transylvania, Romania. It has a population of 1,774 as of 2021, and is made up of fifteen ...

'' *'' Synhoria'' Tribe Nemognathini *'' Cochliophorus'' *'' Euzonitis'' *'' Gnathium'' *'' Gnathonemula'' *'' Leptopalpus'' *'' Megatrachelus'' *'' Nemognatha'' *''

Palaestra A palaestra ( or ; also (chiefly British) palestra; ) was any site of a Greek wrestling school in antiquity. Events requiring little space, such as boxing and wrestling, occurred there. ''Palaistrai'' functioned both independently and as a part ...

'' *'' Palaestrida'' *'' Pseudozonitis'' *'' Rhyphonemognatha'' *'' Stenodera'' *'' Zonitis'' *'' Zonitodema'' *'' Zonitolytta'' *'' Zonitomorpha'' *'' Zonitoschema'' Tribe Sitarini *'' Allendeselazaria'' *'' Apalus'' *'' Ctenopus'' *'' Glasunovia'' *'' Nyadatus'' *'' Sitaris'' *'' Sitarobrachys'' *'' Stenoria'' Genera ''

'' *'' Hornia'' *'' Onyctenus'' *'' Sitaromorpha'' *'' Tricrania''

Subfamily Tetraonycinae

Tribe Tetraonycini *'' Meloetyphlus'' *'' Opiomeloe'' *'' Tetraonyx''

References

External links

Blister Beetle Intoxication: Cantharidin Poisoningmeloidae.com
UF / IFAS Featured Creatures
striped blister beetle, ''Epicauta vittata''
UF / IFAS Featured Creatures
Beetle mania as 'extinct' insect found on Scots isle

Ever so Strange: Blister Beetles Mylabris Pustulata Orange Blister Beetle found in Farms near Nagpur, Maharashtra, India
{{Authority control Poisonous animals