''Phlebotomus'' is a
genus of "
sand flies
Sandfly (or sand fly) is a colloquial name for any species or genus of flying, biting, blood-sucking dipteran (fly) encountered in sandy areas. In the United States, ''sandfly'' may refer to certain horse flies that are also known as "greenhea ...
" in the
Diptera family
Psychodidae
Psychodidae, called drain flies, sink flies, filter flies, sewer flies, or sewer gnats, is a family of true flies. Some genera have short, hairy bodies and wings giving them a "furry" moth-like appearance, hence one of their common names, moth f ...
. In the past, they have sometimes been considered to belong in a separate family,
Phlebotomidae
Psychodidae, called drain flies, sink flies, filter flies, sewer flies, or sewer gnats, is a family of true flies. Some genera have short, hairy bodies and wings giving them a "furry" moth-like appearance, hence one of their common names, moth f ...
, but this alternative classification has not gained wide acceptance.
Epidemiology
In the
Old World
The "Old World" is a term for Afro-Eurasia that originated in Europe , after Europeans became aware of the existence of the Americas. It is used to contrast the continents of Africa, Europe, and Asia, which were previously thought of by th ...
, ''Phlebotomus'' sand flies are primarily responsible for the transmission of
leishmaniasis,
[ an important parasitic disease, while transmission in the New World, is generally via sand flies of the genus '' Lutzomyia''.] The protozoa
Protozoa (singular: protozoan or protozoon; alternative plural: protozoans) are a group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic tissues and debris. Histo ...
n parasite itself is a species of the genus '' Leishmania''. Leishmaniasis normally finds a mammalian reservoir in rodents
Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are roden ...
and other small animals such as canids
Canidae (; from Latin, ''canis'', " dog") is a biological family of dog-like carnivorans, colloquially referred to as dogs, and constitutes a clade. A member of this family is also called a canid (). There are three subfamilies found within th ...
(canine leishmaniasis
Canine leishmaniasis (LEESH-ma-NIGH-ah-sis) is a zoonotic disease (see human leishmaniasis) caused by ''Leishmania'' parasites transmitted by the bite of an infected phlebotomine sandfly. Canine leishmaniasis was first identified in Europe in 190 ...
) and hyraxes. The female sand fly carries the ''Leishmania'' protozoa from infected animals after feeding, thus transmitting the disease, while the male feeds on plant nectar.
The parasite ''Leishmania donovani
''Leishmania donovani'' is a species of intracellular parasites belonging to the genus ''Leishmania'', a group of haemoflagellate kinetoplastids that cause the disease leishmaniasis. It is a human blood parasite responsible for visceral leishman ...
'' is the main causative agent of visceral leishmaniasis (VL) in India, Nepal, and Bangladesh, where it is transmitted by the sand flies of the species ''Phlebotomus argentipes''. This species of sand flies was on the brink of elimination in India during the 1960s following the widespread use of DDT
Dichlorodiphenyltrichloroethane, commonly known as DDT, is a colorless, tasteless, and almost odorless crystalline chemical compound, an organochloride. Originally developed as an insecticide, it became infamous for its environmental impacts. ...
for malaria control. However, there was a resurgence in their population a decade later.
''Phlebotomus'' species are also vectors for bartonellosis
Bartonellosis is an infectious disease produced by bacteria of the genus ''Bartonella''.
''Bartonella'' species cause diseases such as Carrión's disease, trench fever, cat-scratch disease, bacillary angiomatosis, peliosis hepatis, chronic bac ...
, verruga peruana, and pappataci fever
Pappataci fever (also known as Phlebotomus fever and, somewhat confusingly, sandfly fever and three-day fever) is a vector-borne febrile arboviral infection caused by three serotypes of Phlebovirus. It occurs in subtropical regions of the East ...
, an arboviral disease caused by sandfly fever viruses such as the Naples and Sicilian strains of the genus '' Phlebovirus'' (family ''Bunyaviridae
''Bunyavirales'' is an order of segmented negative-strand RNA viruses with mainly tripartite genomes. Member viruses infect arthropods, plants, protozoans, and vertebrates. It is the only order in the class ''Ellioviricetes''. The name ''Bunyavir ...
''), which also includes the closely related Toscana virus.
In Egypt, two species of medical importance are ''Phlebotomus papatasii'' and ''P. langerni''. These flies are short-lived. Females are bloodsuckers at night; males feed on plant juices. Adults are poor fliers, they usually hop for short distances.
Morphology
Adults are about 1.5–3.0 mm long and yellowish in colour, with conspicuous black eyes, and hairy bodies, wings, and legs. The oval lanceolate wings are carried erect on the humped thorax.
Males possess long prominent genital terminalia known as claspers.
Females have a pair of anal recti.
Lifecycle
Batches of thirty to seventy eggs are laid in cracks and holes in the ground, in crevices in masonry and among leaf litter. The eggs require a humid environment to avoid desiccation, and hatch within about twenty days. The larvae are mainly scavengers, consuming fungi, leaf mould, rotting vegetation and detritus. The larvae are recognisable by their black heads, greyish twelve segmented bodies and conspicuous feathery, branching bristles on head and body, and two pairs of long hairs on the tip of the abdomen. The larvae pass through four instars over the course of three to four weeks, before selecting an upright position and pupating, with the final larval skin remaining attached to the pupa, the long hairs protruding. In cooler climates, the larvae may diapause
In animal dormancy, diapause is the delay in development in response to regular and recurring periods of adverse environmental conditions.Tauber, M.J., Tauber, C.A., Masaki, S. (1986) ''Seasonal Adaptations of Insects''. Oxford University Press I ...
over winter. Adults emerge from the pupae after about one to two weeks. The whole cycle takes thirty to sixty days unless the larvae diapause, when it may take four or five months. Laboratory colonies of several ''Phlebotomus'' species have been established for experimental study of their biology, behaviour, mutual relations with disease agents, and for testing methods of vector control.[ ]
Behaviour
The adult flies are nocturnal, spending the day sheltering in dark humid places such as on bark, among foliage, among leaf litter, in animal burrows, in termite mounds, and in cracks and crevices. At nightfall they emerge to feed on sugary secretions and plant sap. The female needs a blood meal before it can reproduce; some species feed on mammals including humans, while others also feed on birds, reptiles and amphibians. The fly is a weak flier and takes short flights to find a victim, adopting a "hopping" style of flight when close to a host. Some sandflies are "exophagic", living entirely out of doors, while others are "endophagic" and invade houses. In the tropics, adults may breed all year round, but in temperate climates the adults die off in the autumn and new adults emerge in the spring. The adults have short mouthparts and are unable to bite through clothing.[
]
References
External links
*
{{Taxonbar, from=Q1709478
Psychodidae
Diptera of Africa
Diptera of Asia
Nematoceran flies of Europe
Nematocera genera
Insect vectors of human pathogens
Insects of North Africa
Insects of the Middle East
Insects of Southeast Asia
Afrotropical realm fauna
Indomalayan realm fauna
Taxa named by Camillo Rondani