The Reduviidae are a large
cosmopolitan family of the
order
Order, ORDER or Orders may refer to:
* Categorization, the process in which ideas and objects are recognized, differentiated, and understood
* Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...
Hemiptera (true bugs). Among the Hemiptera and together with the
Nabidae almost all species are terrestrial
ambush predators: most other predatory Hemiptera are aquatic. The main examples of nonpredatory Reduviidae are some blood-sucking
ectoparasites in the subfamily
Triatominae. Though spectacular exceptions are known, most members of the family are fairly easily recognizable; they have a relatively narrow neck, sturdy build, and a formidable curved
proboscis
A proboscis () is an elongated appendage from the head of an animal, either a vertebrate or an invertebrate. In invertebrates, the term usually refers to tubular mouthparts used for feeding and sucking. In vertebrates, a proboscis is an elonga ...
(sometimes called a
rostrum). Large specimens should be handled with caution, if at all, because they sometimes defend themselves with a very painful stab from the proboscis.
Taxonomy
The Reduviidae are members of the suborder
Heteroptera of the order
Hemiptera. The family members are almost all predatory, except for a few blood-sucking species, some of which are important as disease vectors. About 7000 species have been described, in more than 20 recognized subfamilies, making it one of the largest families in the Hemiptera.
The name Reduviidae is derived from the
type genus, ''
Reduvius''. That name, in turn, comes from the
Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power ...
''
reduvia'', meaning "
hangnail" or "remnant". Possibly this name was inspired by the lateral flanges on the abdomen of many species.
Common
genera include:
* ''
Lopodytes
''Lopodytes'' Rondani 1867Maldonado Capriles, Jenaro. University of Puerto Rico Catalogue of the Reduviidae of the World. Special Edition of the Caribbean Journal of Science, 199/ref> is a genus in the family Reduviidae, the assassin bugs. Membe ...
''
* ''
Melanolestes''
* ''
Platymeris''
* ''
Pselliopus
''Pselliopus'' is a common genus of assassin bugs (Reduviidae), in the subfamily Harpactorinae. The genus is restricted to the New World, with 27 species described. Some species, such as ''Pselliopus barberi'', are conspicuous because of their b ...
''
* ''
Psyttala''
* ''
Rasahus''
* ''
Reduvius''
* ''
Rhiginia''
* ''
Sinea''
* ''
Zelus''
While members of most subfamilies have no
common name
In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contra ...
s other than assassin bugs, among the many subfamilies are a few with their own common names that are reasonably widely recognized, such as:
* Ambush bugs - subfamily
Phymatinae
* Thread-legged bugs - subfamily
Emesinae
The Emesinae, or thread-legged bugs, are a subfamily of the Reduviidae (i.e., assassin bugs). They are conspicuously different from the other reduviids by their very slender body form. They are stalking, predatory insects that can be collected on ...
, including the genus ''
Emesaya
''Emesaya'' is a genus of true bug in the subfamily Emesinae
The Emesinae, or thread-legged bugs, are a subfamily of the Reduviidae (i.e., assassin bugs). They are conspicuously different from the other reduviids by their very slender body for ...
''
* Kissing bugs (or cone-headed bugs) - subfamily
Triatominae, unusual in that most species are blood-suckers and several are important disease vectors
* Wheel bugs - genus ''
Arilus'', including the common North American species ''
Arilus cristatus
''Arilus cristatus'', also known as the North American wheel bug, is a species of large assassin bug in the family Reduviidae and the only species of wheel bug found in the United States. It is one of the largest terrestrial true bugs in North Am ...
''
* Grass assassin bugs - genus
Lopodytes
''Lopodytes'' Rondani 1867Maldonado Capriles, Jenaro. University of Puerto Rico Catalogue of the Reduviidae of the World. Special Edition of the Caribbean Journal of Science, 199/ref> is a genus in the family Reduviidae, the assassin bugs. Membe ...
Morphology
Adult insects range from roughly 12 to 36 mm, depending on the species. They most commonly have an elongated head with a distinct narrowed 'neck', long legs, and prominent, segmented, tubular mouthparts, most commonly called the proboscis, but some authors use the term "rostrum". Most species are bright in colour with hues of brown, black, red, or orange.
The most distinctive feature of the family is that the tip of the proboscis fits into a ridged groove in the
prosternum
The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum ( dorsal), the prosternum (ventral), and the propleuron ( lateral) on ...
, where it can be used to produce sound by
stridulation. Sound is made by rasping the proboscis against ridges in this groove
stridulitrum
Stridulation is the act of producing sound by rubbing together certain body parts. This behavior is mostly associated with insects, but other animals are known to do this as well, such as a number of species of fish, snakes and spiders. The mech ...
(stridulatory organ). These sounds are often used to discourage predators. When harassed, many species can deliver a painful stab with the proboscis, injecting venom or digestive juices. The effects can be intensely painful and the injection from some species may be medically significant.
Feeding
Predatory Reduviidae use the long rostrum to inject a lethal
saliva that liquefies the insides of the prey, which are then sucked out. The saliva contains enzymes that digest the tissues they swallow. This process is generally referred to as
extraoral digestion.
[ ] The saliva is commonly effective at killing prey substantially larger than the bug itself.
The legs of some Reduviidae have areas covered in tiny hairs that aid in holding onto their prey while they feed. Others, members of the subfamily
Phymatinae in particular, have forelegs that resemble those of the
praying mantis, and they catch and hold their prey in a similar way to mantises.
As
nymphs, some species cover and
camouflage
Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the b ...
themselves effectively with debris or the remains of dead prey insects. The nymphal instars of the species ''
Acanthaspis pedestris
''Acanthaspis pedestris'' is a species of assassin bug
The Reduviidae are a large cosmopolitan family of the order Hemiptera (true bugs). Among the Hemiptera and together with the Nabidae almost all species are terrestrial ambush predators: m ...
'' present one good example of this behaviour where they occur in
Tamil Nadu
Tamil Nadu (; , TN) is a state in southern India. It is the tenth largest Indian state by area and the sixth largest by population. Its capital and largest city is Chennai. Tamil Nadu is the home of the Tamil people, whose Tamil languag ...
in India. Another well-known species is ''
Reduvius personatus'', known as the masked hunter because of its habit of camouflaging itself with dust. Some species tend to feed on pests such as
cockroach
Cockroaches (or roaches) are a Paraphyly, paraphyletic group of insects belonging to Blattodea, containing all members of the group except termites. About 30 cockroach species out of 4,600 are associated with human habitats. Some species are we ...
es or
bedbug
Bed bugs are insects from the genus ''Cimex'' that feed on blood, usually at night. Their bites can result in a number of health impacts including skin rashes, psychological effects, and allergy, allergic symptoms. Bed bug bites may lead to ski ...
s and are accordingly popular in regions where people regard their hunting as beneficial. ''Reduvius personatus'' is an example, and some people breed them as pets and for pest control. Some assassin bug subfamilies are adapted to hunting certain types of prey; for example, the
Ectrichodiinae eat
millipedes, and
feather-legged bugs eat ants. A spectacular example of the latter is ''
Ptilocnemus lemur
''Ptilocnemus lemur'' is a species of feather-legged bug in the family Reduviidae native to Australia. Commonly known as the feather-legged assassin bug, it is a predator with a specialized gland called a trichome that it uses to attract and para ...
'', an Australian species in which the adult attacks and eats ants, but the nymph waits until the ant bites the feathery tufts on its hind legs, upon which it whips around and pierces the ant's head with its proboscis, and proceeds to feed.
Some research on the nature of the venom from certain Reduviidae is under way. The saliva of ''
Rhynocoris marginatus
''Rhynocoris marginatus'' is a species of assassin bug in the family Reduviidae. It is a predator of other insects and is found in Asia. Crops in India on which it has been found feeding on pests include sugarcane, pigeon pea, cardamom, cotton, ...
'' showed some insecticidal activity ''
in vitro
''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in biology and ...
'', in tests on lepidopteran pests. The effects included reduction of food consumption, assimilation, and use. Its antiaggregation factors also affected the aggregation and mobility of haemocytes.
The saliva of the species ''
Rhynocoris marginatus
''Rhynocoris marginatus'' is a species of assassin bug in the family Reduviidae. It is a predator of other insects and is found in Asia. Crops in India on which it has been found feeding on pests include sugarcane, pigeon pea, cardamom, cotton, ...
'' (Fab.) and ''
Catamirus brevipennis'' (Servile) have been studied because of their activity against human pathogenic Gram-negative bacteria (including strains of ''
Escherichia coli
''Escherichia coli'' (),Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. also known as ''E. coli'' (), is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus '' Esc ...
'', ''
Pseudomonas aeruginosa'', ''
Proteus vulgaris'', and ''
Salmonella typhimurium'') and the Gram-positive (''
Streptococcus pyogenes
''Streptococcus pyogenes'' is a species of Gram-positive, aerotolerant bacteria in the genus '' Streptococcus''. These bacteria are extracellular, and made up of non-motile and non-sporing cocci (round cells) that tend to link in chains. They ...
'').
Some species are bloodsuckers rather than predators, and they are accordingly far less welcome to humans. ''
Triatoma'' species and other members of the subfamily
Triatominae, such as ''
Rhodnius
''Rhodnius'' is a genus of assassin bugs in the subfamily Triatominae (the kissing bugs), and is an important vector in the spread of Chagas disease. The ''Rhodnius'' species were important models for Sir Vincent Wigglesworth's studies of in ...
'' species, ''
Panstrongylus megistus'', and ''
Paratriatoma hirsuta
''Paratriatoma'' is a genus of kissing bugs in the family Reduviidae
The Reduviidae are a large cosmopolitan family of the order Hemiptera (true bugs). Among the Hemiptera and together with the Nabidae almost all species are terrestrial ambus ...
'', are known as kissing bugs, because they tend to bite sleeping humans in the soft tissue around the lips and eyes. A more serious problem than their bites is the fact that several of these
haematophagous Central and South American species transmit the potentially fatal
trypanosomal
Chagas disease, sometimes called American trypanosomiasis. This results in the death of 12,000 people a year.
Phylogeny and evolutionary history
Current taxonomy is based on morphological characteristics. The first cladistic analysis based on molecular data (mitochondrial and nuclear ribosomal DNA) was published in 2009 and called into question the monophyly of some current groups, such as the
Emesinae
The Emesinae, or thread-legged bugs, are a subfamily of the Reduviidae (i.e., assassin bugs). They are conspicuously different from the other reduviids by their very slender body form. They are stalking, predatory insects that can be collected on ...
. Reduviidae are monophyletic, and the "Phymatine Complex" is consistently recovered as the sister to the higher Reduviidae, which includes 90 percent of the reduviid species diversity. The origin of the species dates to around the middle Jurassic. The oldest fossils of the family are from the
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', ...
(
Cenomanian) aged
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. ...
, represented by
nymphs and the genus ''
Paleotriatoma,'' belonging to the subfamily
Triatominae.
Example species
* ''
Arilus cristatus
''Arilus cristatus'', also known as the North American wheel bug, is a species of large assassin bug in the family Reduviidae and the only species of wheel bug found in the United States. It is one of the largest terrestrial true bugs in North Am ...
''
References
External links
Reduviidae Systematics Research at UC RiversideVideo of Reduviid from ThailandReduviidae at the Encyclopedia of Life
{{Authority control
Heteroptera families
Taxa named by Pierre André Latreille