Subfamily: Phlebotominae (sandflies)
> Eukaryotes >
Metazoa (animals) > Bilateria > Ecdysozoa
> Panarthropoda > Tritocerebra > Phylum:
Arthopoda > Mandibulata >
Atelocerata > Panhexapoda >
> Insecta (insects) > Dicondyla > Pterygota >
Metapterygota > Neoptera > Eumetabola > Holometabola > Panorpida > Antliophora
> Diptera (flies)
Sandflies (Phlebotominae) are blood suckers and
their larvae inhabit places where there is high organic matter such as in animal
burrows, termite hills and tree holes. Sandflies are best known as vectors of trypanosome species in
Leishmania, causing diseases collectively known as
Sandflies belong to the fly family Psychodidae,
members of which are characterised by their densely hairy wings which give them
a moth-like appearance. Phlebotomines are distinguished from other members of
the family by the way they hold their wings above the body in a vertical V
(see picture of member of other subfamily showing
how wings are held flat near the body).
Diversity and distribution
There are about 700 species of phlebotomine sandflies of
which about 70 are considered to transmit diseases to people. The term sandflies
is also sometimes confusingly used for other small biting flies, especially ceratopogonid
flies of the genus Culicoides. It is used below exclusively for the
Phlebotominae. Sandflies are found mainly in the tropics with a few species also
found in the temperate regions. They occur in a wide range of habitats and
species often have very specific habitat requirements. In the Old World,
leishmaniasis is found mainly in dry, semi-arid areas whereas in the New World,
this disease occurs mainly in tropical forests and savannas.
- Genus: Brumptomyia
- Genus: Lutzomyia. The only genus of
phlebotomine flies that suck blood from people in the New World.
- Genus: Warileya
Disease organisms transmitted
Protozoan parasites that cause visceral leishmaniasis (kala-azar)
and various types of cutaneous leishmaniasis (e.g. oriental sore, espundia)
causing the disease bartonellosis (Oroya fever, Carrion's disease) in
northwestern South America (Peru, Colombia and Ecuador).
- Sandfly Fever Virus. Transmitted by sandflies in
North Africa and the Middle East.
- Toscana virus. Occurs in the northern and
- Chagres and Punta Toro viruses. Occur in the New
It is difficult studying the life cycle of sandflies
because the larvae are tiny and don't live in well defined places, like mosquito
larvae. The entire life cycle takes 20-40 days except in diapausing species
(i.e. those that stop developing when conditions become too cold).
Eggs. The female lays 30-70 eggs by scattering them
around a potential breeding site. They hatch within 1-2 weeks.
Larvae. Larvae feed on dead organic matter and are
found in damp places containing organic matter such as cracks in walls or rock,
animal burrows and shelters, caves, or in leaf litter. In regions with cool
winters, larvae diapause in the fourth (final) instar.
Pupae. Pupal development takes 5-10 days.
Adults. Emerge from the pupae in darkness, often
just before dawn. Only the female sucks blood, the food being used for egg
production. Both males and females feed on sugary secretions from plants or from
honeydew produced by homopteran bugs. Mating takes place at or near hosts: the
males congregate in leks on or near the host and produce sex pheromones. Females
home in on hosts using both host odour and the odour produced by the males.
Vibration of the wings by males can be important in encouraging females to
Adults are mainly active in the early morning, evening and
at night although they can bite during the day if disturbed. When innactive,
adult sandflies have habitat-specific resting sites that are characteristic of
particular species. One of the main ways in which entomologists study sandflies
is by locating and studying them at their resting sites. Resting sites are often
similar or near to the larval breeding sites and are usually places that are
cool, humid and dark. Sandflies are able to survive in dry environments by
withdrawing to cool, humid resting sites during the day and then becoming active
at night when ambient temperatures drop and humidity increases.
Seasonal activity of adults is affected mainly by
temperature and rainfall.
- Spraying of residual insecticides on surfaces in the
home. This has been the main way used for controlling sandflies but is
obviously ineffective for those species which bite away from the home such
as those in South American forests. This control technique is also used for
killing Anopheles mosquitoes
that transmit malaria and is some regions it is effective in reducing
both malaria and leishmaniasis.
- Killing of reservoir species. Certain species of
mammals can act as important reservoirs of Leishmania and by killing
the reservoir species that are living near human habitation, disease rates
can be decreased. For instance, rodenticides have been used against the
Great Gerbil Rhombomys opimus in Central Asia.
- Insecticide spraying of larval habitat. This is
usually not possible because, usually, so little is known about where the
Lane, R.P. 1993. Sandflies (Phlebotominae). In: Medical
Insects and Arachnids (eds R.P. Lane and R.W. Crosskey). Chapman and
Hall, London, pp. 78-119.